JP2018503942A - Membrane electrode assembly - Google Patents

Abstract

A membrane electrode assembly comprising an oxygen evolution reaction catalyst disposed on a gas supply layer (100, 700) or between a gas supply layer (100, 700 and a gas dispersion layer (200, 600). The membrane electrode assembly described herein is useful, for example, in electrochemical devices such as fuel cells.

Description

Cross-reference of related applications

  This application claims the benefit of US Provisional Patent Application No. 62/091851 filed on December 15, 2014 and No. 62/096097 filed on December 23, 2014. The entire disclosure of which is incorporated herein by reference.

  This invention was made with the support of the US Government under a cooperative contract DE-EE0000456 with the support of the US Department of Energy. The government has certain rights in the invention.

  Proton exchange membrane fuel cells, also known as polymer electrolyte membrane (PEM) fuel cells (PEMFC), convert the electrochemical energy released during hydrogen and oxygen electrode reactions into electrical energy. The hydrogen stream is transported to the anode side of the membrane electrode assembly (MEA). The hydrogen oxidation reaction (HOR), which is a half-cell reaction at the anode, divides hydrogen into protons and electrons. Newly generated protons pass through the polymer electrode membrane to the cathode side. The electrons travel along the external load circuit to the cathode side of the MEA, thereby producing a fuel cell current output. On the other hand, an oxygen stream (typically in air) is transported to the cathode side of the MEA. On the cathode side, oxygen molecules are reduced by electrons that reach through the external circuit, and combine with protons that permeate the polymer electrolyte membrane to form water molecules. This cathode half-cell reaction is an oxygen reduction reaction (ORR). Both half-cell reactions are typically catalyzed by platinum-based materials. Since each battery produces approximately 1.1 volts, the batteries are combined to create a stack to reach the desired voltage for a particular application. Each cell is separated by a bipolar plate, which also provides a hydrogen fuel supply channel and a current extraction method. PEM fuel cells are considered to have the highest energy density of all fuel cells and have the fastest start-up time (less than 1 second) due to the nature of the reaction. Therefore, this tends to be preferred for applications such as automobiles, portable power supplies, and standby power applications.

  PEM fuel cells operating in automotive applications typically experience thousands of start / stop events over many years of operation. During this repeated fuel cell start / stop cycle transient, and during other abnormal fuel cell operating conditions (eg, cell reversal caused by local fuel depletion), the electrode operates normally. The value and the thermodynamic stability of water may be significantly exceeded (i.e.> 1.23 V) temporarily at a relatively high positive potential. These transient high potential pulses can lead to degradation of the catalyst layer. Moreover, about a carbon supported catalyst, corrosion of a carbon support body may arise.

  Incorporating an oxygen evolution reaction (OER) catalyst to favor the electrolysis of water over carbon corrosion or catalyst degradation / dissolution reduces the cell voltage and fuel cells during transient conditions It is a relatively new material-based strategy to achieve the durability of Ru has been observed to exhibit excellent OER activity, but is preferably stabilized. While it is well known that Ir can stabilize Ru, it has been observed that Ir itself exhibits good OER activity.

Prior to startup, the anode flow field is typically filled with air. During startup of the fuel cell, the gas is switched to hydrogen from the air, as a result, H ₂ moves through the anode flow field - occurs air front. When stopping the fuel cell, H ₂ is formed by switching a gas - air front moves in the opposite direction through the anode flow field. Go and are H ₂ - hydrogen and oxygen in air front, especially when the catalyst such as platinum is present, recombine, it is known that in some cases to produce water. This reaction can be relatively intense.

  It is desirable to reduce the adverse effects on MEA performance from switching gases.

In one aspect, the disclosure provides
A first gas supply layer;
Optionally a first gas dispersion layer;
An anode catalyst layer comprising a first catalyst;
A membrane,
A cathode catalyst layer comprising a second catalyst;
Optionally a second gas dispersion layer;
A second gas supply layer in order,
The first gas supply layer has a first main surface and a second main surface that are substantially opposed to each other,
The anode catalyst layer has a first main surface and a second main surface that are substantially opposed to each other, and the second main surface of the first gas supply layer is more anode catalyst than the second main surface of the first anode catalyst layer. Closer to the first major surface of the layer,
The membrane has a first major surface and a second major surface that are substantially opposed, wherein the second major surface of the anode catalyst layer is closer to the first major surface of the membrane than the second major surface of the membrane;
The cathode catalyst layer has a first main surface and a second main surface substantially opposed to each other, and the second main surface of the membrane is closer to the first main surface of the cathode catalyst layer than to the second main surface of the cathode catalyst layer. ,
The second gas supply layer has a first main surface and a second main surface that are substantially opposed to each other, and the second main surface of the cathode catalyst layer is also second than the second main surface of the second gas supply layer. Closer to the first main surface of the gas supply layer of
At least one of the following layers:
A layer containing an oxygen generation reaction catalyst disposed on the first main surface of the first gas supply layer;
A first gas supply layer containing an oxygen generation reaction catalyst;
A layer containing an oxygen generation reaction catalyst disposed on the second main surface of the first gas supply layer;
A layer containing an oxygen generation reaction catalyst disposed between the first gas supply layer and the first gas dispersion layer;
A layer containing an oxygen generation reaction catalyst disposed on the first main surface of the first gas dispersion layer;
A first gas dispersion layer comprising an oxygen evolution reaction catalyst;
A layer containing an oxygen generation reaction catalyst disposed on the second main surface of the first gas dispersion layer;
A layer containing an oxygen generation reaction catalyst disposed on the first main surface of the second gas dispersion layer;
A second gas dispersion layer containing an oxygen generation reaction catalyst;
A layer containing an oxygen generation reaction catalyst disposed on the second main surface of the second gas dispersion layer;
A layer containing an oxygen generation reaction catalyst disposed between the second gas supply layer and the second gas dispersion layer;
A layer containing an oxygen generation reaction catalyst disposed on the first main surface of the second gas supply layer;
A second gas supply layer containing an oxygen generation reaction catalyst,
A membrane electrode assembly is provided wherein there is at least one of a layer comprising an oxygen evolution reaction catalyst disposed on a second major surface of a second gas supply layer.

  Unexpectedly, an oxygen evolution reaction (OER) catalyst (eg, Ru, Ir, RuIr or an oxide thereof) and a Pt-based hydrogen oxidation reaction (HOR) catalyst on the anode side of a hydrogen PEM fuel cell or Pt on the cathode side By physically separating the oxygen reduction reaction (ORR) catalyst, the substantial durability of the catalyst associated with gas switching events such as start / stop or cell reversal (due to local fuel depletion) Have found that this improvement can be achieved. A further advantage of the membrane electrode assembly (MEA) described herein is that the OER catalyst can be varied independently of the choice of anode and cathode catalyst layers to be joined to the polymer electrolyte membrane. Thus, the OER catalyst can be used with an electrolyte membrane with a catalyst layer having various HOR catalyst layers and ORR catalyst layers such as Pt on carbon or Pt on a nanostructured thin film support. OER catalyst loading, processing and performance enhancement aids can be tailored to meet specific customer needs such as specific anode, cathode, loading requirements, and the like. This technique also includes various electrolyte membranes with a catalyst layer (CCM) in which the OER catalyst on the gas supply layer or the gas dispersion layer or in the gas supply layer or the gas dispersion layer is one component and another catalyst layer is added thereto. ) And MEA configuration.

  The membrane electrode assembly described herein is useful, for example, in fuel cells.

1 is a schematic diagram of an exemplary embodiment of a membrane electrode assembly described herein. FIG.

1 is a schematic diagram of an exemplary embodiment of a fuel cell having a membrane electrode assembly as described herein. FIG.

It is a plot which shows the cell output voltage with respect to standard hydrogen electrode _{ESHE as} a function of time about Examples 1-6 and Comparative Examples AC.

  Referring to FIG. 1, an exemplary membrane electrode assembly described herein includes a first gas supply layer 100, an optional first gas dispersion layer 200, and an anode catalyst layer 300 including a first catalyst. A membrane catalyst 400, a cathode catalyst layer 500 containing a second catalyst, an optional second gas dispersion layer 600, and a second gas supply layer 700 in this order.

  The first gas supply layer 100 has a first main surface 101 and a second main surface 102 that are substantially opposed to each other. The anode catalyst layer 300 has a first main surface 301 and a second main surface 302 that are substantially opposed to each other. The second main surface 102 of the first gas supply layer 100 is closer to the first main surface 301 of the anode catalyst layer 300 than the second main surface 302 of the first anode catalyst layer 300.

  The film 400 has a first main surface 401 and a second main surface 402 that are substantially opposed to each other. The second major surface 302 of the anode catalyst layer 300 is closer to the first major surface 401 of the membrane than the second major surface 402 of the membrane 400. The cathode catalyst layer 500 has a first main surface 501 and a second main surface 502 that are substantially opposed to each other. The second main surface 402 of the membrane 400 is closer to the first main surface 501 of the cathode catalyst layer 500 than the second main surface 502 of the cathode catalyst layer 500.

  The second gas supply layer 700 has a first main surface 701 and a second main surface 702 that are substantially opposed to each other. The second main surface 502 of the cathode catalyst layer 500 is closer to the first main surface 701 of the second gas supply layer 700 than the second main surface 702 of the second gas supply layer 700.

The exemplary membrane electrode assembly 9 also includes
A layer 1100 comprising an oxygen generation reaction (OER) catalyst disposed on the first major surface 101 of the first gas supply layer 100;
A first gas supply layer 100 containing an oxygen generation reaction catalyst,
A layer 1150 including an oxygen generation reaction catalyst disposed on the second main surface 102 of the first gas supply layer 100;
A layer 1200 including an oxygen generation reaction catalyst disposed between the first gas supply layer 100 and the first gas dispersion layer 200;
A layer 1250 including an oxygen generation reaction catalyst disposed on the first major surface 201 of the first gas dispersion layer 200;
A first gas dispersion layer 200 containing an oxygen generation reaction catalyst,
A layer 1300 including an oxygen generation reaction catalyst disposed on the second major surface 202 of the first gas dispersion layer 200;
A layer 1400 including an oxygen generation reaction catalyst disposed on the first major surface 601 of the second gas dispersion layer 600;
A second gas dispersion layer 600 containing an oxygen generation reaction catalyst,
A layer 1500 including an oxygen generation reaction catalyst disposed on the second major surface 602 of the second gas dispersion layer 600;
A layer 1550 including an oxygen generation reaction catalyst disposed between the second gas supply layer 600 and the second gas dispersion layer 700;
A layer 1600 including an oxygen generation reaction catalyst disposed on the first main surface 701 of the second gas supply layer 700;
A second gas supply layer 700 containing an oxygen generation reaction catalyst,
At least one of layers 1700 including an oxygen generation reaction catalyst disposed on the second main surface 702 of the second gas supply layer 700 is provided. As shown, the oxygen evolution reaction catalyst is present in the layer 1100.

  When a membrane electrode assembly (MEA) is used in an electrochemical device such as a fuel cell, the oxygen generating reaction catalyst 105 is preferably in electrical contact with an external circuit. This is possible because in many polymer electrolyte membrane (PEM) fuel cell configurations, the first gas supply layer 100 and the second gas supply layer 700 are conductive.

  Without being bound by theory, in order to successfully incorporate an OER catalyst, it is desirable to prevent the OER catalyst from interfering with or affecting the Pt hydrogen oxidation reaction (HOR) or vice versa. Conceivable.

  Membrane electrode assemblies described herein and devices incorporating the membrane electrode assemblies described herein are generally manufactured using techniques well known in the art, but may include components described herein or Modified by option.

  The gas supply layer generally transports gas evenly to the electrodes and in some embodiments conducts electricity. The gas supply layer also removes water in either vapor or liquid form. An exemplary gas supply layer is a gas diffusion layer, sometimes referred to as a macroporous gas diffusion backing (GDB). Examples of the raw material of the gas supply layer include carbon fibers in the form of nonwoven paper or woven fabric, which are randomly oriented to form a porous layer. Non-woven carbon paper is, for example, from Mitsubishi Rayon Co., Ltd. (Tokyo) under the trade name “Graphyl U-105”, from Toray Industries, Inc. (Tokyo) under the trade name “TORAY”, and from AvCarb Material under the trade name “AVCARB”. Solutions (Lowell, Massachusetts, USA) from SGL Group, the Carbon Company (Germany, Wiesbaden) under the trade name “SIGRACET”, and Freudenberg FCCT SE & Co. Under the trade name “Freudenberg”. KG, Fuel Cell Component Technologies (Weinheim, Germany) is commercially available from Engineered Fibers Technology (EFT) (Shelton, Connecticut, USA) under the trade name "Spectracarb GDL". Carbon woven fabrics, for example, under the trade names of “EC-CC1-060” and “EC-AC-CLOTH”, ElectroChem. , Inc. (Uban, Massachusetts, USA) under the trade names “ELAT-LT” and “ELAT” under the name of NuVant Systems Inc. (Crown Point, Indiana, USA) from BASF Fuel Cell GmbH (North America) under the trade name “E-TEK ELAT LT”, and under the trade name “ZOLTEK CARBON CLOTH” from Zoltek Corp. (St. Louis, Missouri, USA).

  The gas dispersion layer further supplies gas to the electrode in a generally more uniform manner and generally protects the catalyst layer and membrane from mechanical defects due to the roughness that may be present in the gas supply layer. In such an embodiment, electricity is passed and the electrical contact resistance with the adjacent catalyst layer is reduced. The gas dispersion layer can also provide a wicking effect of liquid water from the catalyst layer to the diffusion layer. An exemplary gas dispersion layer is a microporous layer. The microporous layer is impregnated with a water-repellent hydrophobic binder (for example, fluoropolymer or fluorinated ethylene propylene resin FEP) and an auxiliary agent such as carbon black in a gas supply layer such as carbon paper or carbon cloth. Alternatively, it can be formed by coating. Carbon paper or carbon cloth is typically first dipped in a solution / emulsion in which a water repellent hydrophobic material is dispersed in a solvent (eg, water or alcohol), then dried and heat treated, and then carbon. After the substrate is coated with the slurry, it is dried and heat-treated. Exemplary fluoropolymers such as PTFE (polytetrafluoroethylene) are available from Ensinger GmbH (Nuflingen, Germany) under the trade name “TECAFLON PTFE NATURAL”, for example, under the trade name “3M DYNEON PTFE TF” (3M Dyneon ( From St. Paul, Minnesota, USA, under the trade name “BAM PTFE”, from Bailey Advanced Materials LLC (Edinburgh, UK), under the trade names “DUPONT PTFE” and “DUPONT TEFLON ETFE”. I. commercially available from du Pont de Nemours (Wilmington, Delaware, USA). (Ethylene-tetrafluoroethylene copolymer) is commercially available from Ensinger GmbH under the trade name “TECAFLON ETFE NATURAL” and 3M Dyneon under the trade name “3M DYNEON”. ETFE (thermoplastic fluororesin) is commercially available from Bailey Advanced Materials LLC under the trade name “BAM ETFE” and E.P.E. under the trade name “DUPONT ETFE”. I. For example, PVDF (polyvinylidene fluoride) is commercially available from du Pont de Nemours under the trade name “TECAFLON PVDF” from Ensinger GmbH, and from 3M DYNEON FLUOROPLASTIC PVDF under the trade name “BAMPVDF”. It is commercially available from Bailey Advanced Materials LLC under the name. An exemplary raw material fluorinated ethylene propylene resin FEP is E.I. under the trade name "DuPont Teflon FEP". I. It is commercially available from Du Pont de Nemours and from Daikin North America LLC under the trade name “NEOFLON Dispersion” (FEP / PFA). Exemplary raw materials for the carbon black powder include acetylene black commercially available from manufacturers including Alfa Aesar (Ward Hill, Mass., USA) or Cabot Corporation (Boston, Mass., USA) under the trade name “VULCAN XC-72”. Oil furnace carbon black commercially available.

Exemplary membranes include polymer electrolyte membranes. Exemplary polymer electrolyte membranes include membranes that include anionic functional groups bonded to a common backbone, which are typically sulfonic acid groups, but carboxylic acid groups, It may contain imide groups, amide groups or other acidic functional groups. The polymer electrolytes used in making the membrane electrode assemblies described herein are typically highly fluorinated and more typically perfluorinated. The polymer electrolyte used in making the membrane electrode assembly described herein is typically a copolymer of tetrafluoroethylene and at least a fluorinated acid functional comonomer. Exemplary polymer electrolytes include E.I. under the trade name “Nafion”. I. Examples thereof include an electrolyte commercially available from du Pont de Nemours (Wilmington, Delaware, USA) and an electrolyte commercially available from Asahi Glass Co., Ltd. under the trade name “Flemion”. Polymer electrolytes are described in copolymers of tetrafluoroethylene (TFE) and, for example, US Pat. Nos. 6,624,328 (Guerra) and 7348088 (Freemeyer et al.), The disclosures of which are incorporated herein by reference. it may be _{FSO 2 CF 2 CF 2 CF 2} CF 2 -O-CF = CF 2. The equivalent weight (EW) of the polymer is typically less than 1200, less than 1100, less than 1000, less than 900 or less than 800.

  The oxygen generating reaction electrocatalyst is involved in the electrochemical oxygen generating reaction. The catalyst material changes and accelerates the chemical reaction rate without being consumed in the reaction process. An electrocatalyst is a specific form of catalyst that acts on the electrode surface, and may be the electrode surface itself. Electrocatalysts can be heterogeneous, such as iridium surfaces, coatings or nanoparticles, or can be uniform, such as dissolved coordination complexes. The electrocatalyst assists the transfer of electrons between the electrode and the reactants and / or promotes intermediate chemical changes represented by the entire semi-reaction equation.

  In general, the oxygen evolution reaction catalyst may be deposited by techniques well known in the art. Exemplary deposition methods include sputtering (including reactive sputtering), atomic layer deposition, organic molecular chemical vapor deposition, molecular beam epitaxy, thermal physical vapor deposition, vacuum deposition by electrospray ionization, and pulsed laser deposition. Examples include techniques that are selected independently from the group. For further general details, see, for example, US Pat. Nos. 5,889,827 (Debe et al.), 6040077 (Debe et al.), And 7,417,741 (Vernstrom et al.), The disclosures of which are incorporated herein by reference. Can be seen). In thermal physical vapor deposition, the target (raw material) is melted or sublimated into a vapor state using an appropriate high temperature (eg, by resistance heating, an electron beam gun or laser), and then the vapor is passed through a vacuum space. The vapor form condenses on the substrate surface. Thermal physical vapor deposition devices are well known in the art, for example, as a metal evaporator or organic molecular evaporator, the product "METAL EVAPOTOROR" (ME-Series) or "Organic Molecular Evaporator (DE-Series)", respectively. Another example of an organic material evaporator includes equipment commercially available from ClearPhys GmbH (Dresden, Germany) under the name "ORGANIC MATERIALS EVAPORATIONOR (ORMA-Series)" Mantis Deposition LTD (Oxfordshire, UK) Commercially available. The catalyst comprising a plurality of alternating layers may be sputtered from a plurality of targets (eg, Ir is sputtered from a first target, Pd is sputtered from a second target, and Ru (if any) is third. Sputtering from a target, etc.), and sputtering from a target (s) containing two or more elements. When the catalyst coating is performed with a single target, the coating layer is deposited on the GDL in a single step so that the condensation heat of the catalyst coating is Au, Co, Fe, Ir, Mn, Ni, Os, Pd, To heat atoms such as Pt, Rh or Ru (if applicable) and to sufficiently heat the substrate surface to form a well-mixed and thermodynamically stable alloy region It may be desirable to provide sufficient surface mobility. Alternatively, for example, the atomic mobility can be increased by providing the substrate with heating or heating the substrate. In some embodiments, the sputtering is at least partially performed in an atmosphere comprising at least a mixture of argon and oxygen, and the ratio of the argon flow to the oxygen flow into the sputtering chamber is at least 113 sccm / 7 sccm (per standard cubic centimeter). Min). Organometallic catalysts can be deposited, for example, by soft landing or reactive landing of mass-selected ions. Soft landing of mass-selected ions is used to move catalytically active metal complexes with organic ligands from the gas phase onto an inert surface. This method can be used to prepare substances with well-defined active sites, thereby allowing surface molecular design to be performed in a highly controlled manner under ambient or conventional vacuum conditions. For further details see, for example, Johnson et al., Anal. See Chem 2010, 82, 5718-5727 and Johnson et al., Chemistry: A European Journal 2010, 16, 14433-14438, the disclosures of which are incorporated herein by reference.

Exemplary catalysts contained in the anode catalyst layer are:
(A) at least one of the elements Au, Co, Fe, Ir, Mn, Ni, Os, Pd, Pt, Rh or Ru,
(B) at least one alloy comprising at least one of Au, Co, Fe, Ir, Mn, Ni, Os, Pd, Pt, Rh or Ru;
(C) at least one composite comprising at least one of Au, Co, Fe, Ir, Mn, Ni, Os, Pd, Pt, Rh or Ru;
(D) at least one oxide, hydrated oxide or hydroxide of at least one of Au, Co, Fe, Ir, Mn, Ni, Os, Pd, Pt, Rh or Ru,
(E) at least one organometallic complex of at least one of Au, Co, Fe, Ir, Mn, Ni, Os, Pd, Pt, Rh or Ru;
(F) at least one carbide of at least one of Au, Co, Fe, Ir, Mn, Ni, Os, Pd, Pt, Rh or Ru,
(G) at least one fluoride of at least one of Au, Co, Fe, Ir, Mn, Ni, Os, Pd, Pt, Rh or Ru;
(H) at least one nitride of at least one of Au, Co, Fe, Ir, Mn, Ni, Os, Pd, Pt, Rh or Ru;
(I) at least one boride of at least one of Au, Co, Fe, Ir, Mn, Ni, Os, Pd, Pt, Rh or Ru;
(J) at least one acid carbide of at least one of Au, Co, Fe, Ir, Mn, Ni, Os, Pd, Pt, Rh or Ru,
(K) at least one oxyfluoride of at least one of Au, Co, Fe, Ir, Mn, Ni, Os, Pd, Pt, Rh or Ru,
(L) At least one oxynitride of at least one of Au, Co, Fe, Ir, Mn, Ni, Os, Pd, Pt, Rh, or Ru, or (m) Au, Co, Fe, Ir, Including at least one of at least one acid boride of at least one of Mn, Ni, Os, Pd, Pt, Rh or Ru (wherein oxide, organometallic complex, boride, carbide) , Fluoride, nitride, oxyboride, oxycarbide, oxyfluoride and oxynitride are present together with Au, Co, Fe, Ir, Mn, Ni, Os, Pd, Pt, Rh or Ru. I want you to understand)

Exemplary oxides include CoO, Co ₂ O ₃ , Co ₃ O ₄ , CoFe ₂ O ₄ , FeO, Fe ₂ O ₃ , Fe ₃ O ₄ , Fe ₄ O ₅ , NiO, Ni ₂ O ₃ , Ni _x Fe _y O _z , Ni _x Co _y O _z , MnO, Mn ₂ O ₃ , Mn ₃ O ₄ , Ir _x O _y can be mentioned, and the valence of Ir can be 2 to 8, for example. Specific exemplary Ir oxides include Ir ₂ O ₃ , IrO ₂ , IrO ₃ and IrO ₄ as well as mixed Ir _x Ru _y O _z , Ir _x Pt _y O _z , Ir _x Rh _y O _{z, Ir x Ru y Pt z} O zz, Ir x Rh y Pt z O zz, Ir x Pd y Pt z O zz, Ir x Pd y O z, Ir x Ru y Pd z O zz, Ir x Rh y Pd _z O _zz or iridium acid Ir-Ru pyrochlore type oxide _{(e.g., Na x Ce y Ir z Ru} zz O 7) can be mentioned. Examples of the Ru oxide include Ru _x1 O _y1 whose valence may be 2 to 8, for example. Specific exemplary Ru _oxide, Ru ₂ O _3, RuO ₂ and RuO ₃ or ruthenate Ru-Ir pyrochlore type oxide _{(e.g., Na x Ce y Ru z Ir} zz O 7) can be mentioned. Exemplary Pd oxides include Pd _x O _y forms where the valence of Pd can be, for example, 1, 2, and 4. Specific exemplary Pd oxides include PdO and PdO ₂ . Other oxides, include Os, Rh or Au oxide _{OsO 2, OsO 4, RhO,} RhO 2, Rh 2 O 3, Rh x O y and _Au 2 _O 3, Au ₂ O and _Au x _{O y} is It is done. Exemplary organometallic complexes include at least one of Au, Co, Fe, Ni, Ir, Pd, Rh, Os, or Ru, and include Au, Co, Fe, Ni, Ir, Pd, Pt, Rh. Or Ru forms a coordinate bond with the organic ligand through the heteroatom (s) or non-carbon atom (s) (eg, oxygen, nitrogen, chalcogen (eg, sulfur and selenium), phosphorus or halide) To do. Exemplary Au, Co, Fe, Ir, Ni, Pd, Pt, Rh, Os or Ru complexes with organic ligands can also be formed through π bonds. Examples of the organic ligand having an oxygen heteroatom include functional groups such as hydroxyl, ether, carbonyl, ester, carboxyl, aldehyde, anhydride, cyclic anhydride, and epoxy. Examples of organic ligands having nitrogen heteroatoms include amines, amides, imides, imines, azides, azines, pyrroles, pyridines, porphyrins, isocyanates, carbamates, carbamides, sulfamates, sulfamides, amino acids and N-heterocyclic carbaine. A functional group is mentioned. Examples of organic ligands having sulfur heteroatoms, so-called thioligands, include thiol, thioketone (thione or thiocarbonyl), thiary, thiophene, disulfide, polysulfide, sulfimide, sulfoximide, and sulfonedimine. . Examples of the organic ligand having a phosphorus heteroatom include functional groups such as phosphine, phosphane, phosphanide, and phosphinidene. Exemplary organometallic complexes include Au, Co, Fe, Ir, Ni, Pd, Pt, Rh, Os, or Ru, either a homofunctional organic ligand or a heterofunctional organic ligand. And homo- and heterobimetallic complexes involved in the coordination bond. Au, Co, Fe, Ir, Ni, Pd, Pt, Rh, Os, or Ru organometallic complexes formed through π coordination bonds include carbon-rich π-conjugated organic ligands (eg, allene, Allyl, diene, carbene and alkynyl). Examples of Au, Co, Fe, Ir, Ni, Pd, Pt, Rh, Os or Ru organometallic complexes are chelates, tweezer molecules, cages, molecular boxes, mobile molecules, macrocycles, prisms, half sandwiches And also known as the metal-organic framework (MOF). Exemplary organometallic compounds comprising at least one of Au, Co, Fe, Ir, Ni, Pd, Pt, Rh, Os or Ru include covalent bonds, ionic bonds or covalent-ionic bond mixed metals -A compound in which Au, Co, Fe, Ir, Ni, Pd, Pt, Rh, Os or Ru is bonded to an organic substance through a carbon bond. Exemplary organometallic compounds also include covalent bonds to heteroatoms (eg, oxygen, nitrogen, chalcogens (eg, sulfur) such as Au, Co, Fe, Ir, Ni, Pd, Pt, Rh, Os, or Ru. And a combination of at least two of the coordination bonds to the organic ligand via selenium, phosphorus or halide). The chemical formula of a stable organometallic complex is typically predictable from the 18 electron rule. The 18-electron rule is based on the fact that the transition metal valence shell consists of 9 valence orbitals that can accommodate a total of 18 electrons, either as bonded or unbonded electron pairs. The combination of these nine atomic orbitals and the ligand orbitals yields nine molecular orbitals that are either metal-ligand bonded or non-bonded. The 18-electron rule is generally not applicable to non-transition metal complexes. The 18-electron rule usefully predicts the chemical formula of low-spin complexes of Cr, Mn, Fe and Co trivalent elements. Well known examples include ferrocene, iron pentacarbonyl, chromium carbonyl and nickel carbonyl. The ligand in the complex determines whether the 18 electron rule is applicable. In general, complexes that follow the 18-electron rule are at least partially composed of “π-acceptor ligands” (also known as π acids). This type of ligand creates a very strong ligand field, thus reducing the energy of the resulting molecular orbitals and advantageously occupying the activation. Typical ligands include olefins, phosphines and CO. The π-acid complex is typically characterized by a low oxidation state metal. The relationship between the oxidation state and the nature of the ligand is explained in the framework of π donation. Exemplary _{carbides, Au 2 C 2, Ni 2} C, Ni 3 C, NiC, Fe 2 C, Fe 3 C, Fe x C y, CoC, Co 2 C, Co 3 C, IrC, IrC 2, _{IrC 4, Ir 4 C 5,} Ir x C y, RuC, Ru 2 C, RhC, PtC, OsC, OsC 3, OsC 2, include _{(MnFe) 3} C and Mn ₃ C. Exemplary fluorides include AuF, AuF ₃ , AuF ₅ , FeF ₂ , FeF ₃ , CoFe ₂ , CoF ₃ , NiF ₂ , IrF ₃ , IrF ₄ , Ir _x F _y , PdF ₃ , PdF ₄ , RhF ₃ , RhF ₄ , RhF ₆ RuF ₃ and OsF ₆ . Exemplary nitrides include Au ₃ N, AuN ₂ , Au _x N _y , Ni ₃ N, NiN, Co ₂ N, CoN, Co ₂ N ₃ , Co ₄ N, Fe ₂ N, Fe ₃ N _x ( Where x = 0.75 to 1.4), Fe ₄ N, Fe ₈ N, Fe ₁₆ N ₂ , IrN, IrN ₂ , IrN ₃ , RhN, RhN ₂ , RhN ₃ , Ru ₂ N, RuN, RuN ₂ , PdN, PdN ₂ , OsN, OsN ₂ , OsN ₄ , Mn ₂ N, Mn ₄ N and Mn ₃ N. Exemplary _{borides, Au x B y, Mn 2} AuB, NiB, Ni 3 B, Ni 4 B 3, CoB, Co 2 B, Co 3 B, FeB, Fe 2 B, Ru 2 B 3, RuB _{2, IrB, Ir x B y} , OsB, Os 2 B 3, OsB 2, RhB, ZrRh 3 B, include NbRh ₃ B and YRh ₃ B. Exemplary acid _{carbide, Au x O y C z,} Ni x O y C z, Fe x O y C z, Co x O y C z, Ir x O y C z, Ru x O y C z, _{Rh x O y C z, Pt} x O y C z, include Pd _x O y _{C z,} and _Os x _O y _{C z.} Exemplary acid _{fluoride, Au x O y F z,} Ni x O y F z, Fe x O y F z, Co x O y F z, Ir x O y F z, Ru x O y F z Rh _x O _y F _z , Pt _x O _y F _z , Pd _x O _y F _z and Os _x O _y F _z . Exemplary _{oxynitride, Au x O y N z,} Ni x O y N z, Fe x O y N z, Co x O y N z, Ir x O y N z, Ru x O y N z , Rh _x O _y N _z , Pt _x O _y N _z , Pd _x O _y N _z and Os _x O _y N _z . Exemplary acid _{boride, Au x O y B z,} Ni x O y B z, Fe x O y B z, Co x O y B z, Ir x O y B z, Ru x O y B z , Rh _x O _y B _z , Pt _x O _y B _z , Pd _x O _y B _z and Os _x O _y B _z . Including these oxides, organometallic complexes, carbides, fluorides, nitrides, oxycarbides, oxyfluorides, oxynitrides, oxyborides, boron-containing nitrides and / or composites containing boron-containing carbides Are within the scope of this disclosure.

Exemplary catalysts contained in the cathode catalyst layer are:
(A ″) at least one of the elements Au, Co, Fe, Ir, Mn, Ni, Os, Pd, Pt, Rh or Ru,
(B ″) at least one alloy comprising at least one of Au, Co, Fe, Ir, Mn, Ni, Os, Pd, Pt, Rh or Ru;
(C ″) at least one composite comprising at least one of Au, Co, Fe, Ir, Mn, Ni, Os, Pd, Pt, Rh or Ru;
(D ″) at least one oxide of at least one of Au, Co, Fe, Ir, Mn, Ni, Os, Pd, Pt, Rh or Ru,
(E ″) at least one organometallic complex of at least one of Au, Co, Fe, Ir, Mn, Ni, Os, Pd, Pt, Rh or Ru,
(F ″) at least one carbide of at least one of Au, Co, Fe, Ir, Mn, Ni, Os, Pd, Pt, Rh or Ru,
(G ″) at least one fluoride of at least one of Au, Co, Fe, Ir, Mn, Ni, Os, Pd, Pt, Rh or Ru,
(H ″) at least one nitride of at least one of Au, Co, Fe, Ir, Mn, Ni, Os, Pd, Pt, Rh or Ru,
(I ″) at least one boride of at least one of Au, Co, Fe, Ir, Mn, Ni, Os, Pd, Pt, Rh or Ru;
(J ″) at least one acid carbide of at least one of Au, Co, Fe, Ir, Mn, Ni, Os, Pd, Pt, Rh or Ru,
(K ″) at least one of Au, Co, Fe, Ir, Mn, Ni, Os, Pd, Pt, Rh or Ru, at least one oxyfluoride, or (l ″) Au, Co, At least one oxynitride of at least one of Fe, Ir, Mn, Ni, Os, Pd, Pt, Rh, or Ru, or (m ″) Au, Co, Fe, Ir, Mn, Ni, Os , Pd, Pt, Rh or Ru, including at least one acid boride (wherein oxide, organometallic complex, boride, carbide, fluoride, nitridation) It should be understood that oxides, oxyborides, oxycarbides, oxyfluorides and oxynitrides are present with Au, Co, Fe, Ir, Mn, Ni, Os, Pd, Pt, Rh or Ru. ).

Exemplary oxides include CoO, Co ₂ O ₃ , Co ₃ O ₄ , CoFe ₂ O ₄ , FeO, Fe ₂ O ₃ , Fe ₃ O ₄ , Fe ₄ O ₅ , NiO, Ni ₂ O ₃ , Ni _x Fe _y O _z , Ni _x Co _y O _z , MnO, Mn ₂ O ₃ , Mn ₃ O ₄ and Ir _x O _y can be mentioned, and the valence of Ir can be 2 to 8, for example. Specific exemplary Ir oxides include Ir ₂ O ₃ , IrO ₂ , IrO ₃ and IrO ₄ as well as mixed Ir _x Ru _y O _z , Ir _x Pt _y O _z , Ir _x Rh _y O _{z, Ir x Ru y PtzO zz} , Ir x Rh y PtzO zz, Ir x Pd y PtzO zz, Ir x Pd y O z, Ir x Ru y PdzO zz, Ir x Rh y PdzO zz or iridium acid Ir-Ru pyrochlore type oxide _{(e.g., Na x Ce y Ir z Ru} zz O 7) can be mentioned. Examples of the Ru oxide include Ru _x1 O _y1 whose valence may be 2 to 8, for example. Specific exemplary Ru _oxide, Ru ₂ O _3, RuO ₂ and RuO ₃ or ruthenate Ru-Ir pyrochlore type oxide _{(e.g., Na x Ce y Ru z Ir} zz O 7) can be mentioned. Exemplary Pd oxides include Pd _x O _y forms where the valence of Pd can be, for example, 1, 2, and 4. Specific exemplary Pd oxides include PdO, PdO ₂ , Os oxides ie OsO ₂ and OsO ₄ , RhO, RhO ₂ , Rh ₂ O ₃ , Au ₂ O ₃ , Au ₂ O and Au _x O _y. Is mentioned. Exemplary organometallic complexes include at least one of Au, Co, Fe, Ni, Ir, Mn, Pd, Pt, Rh, Os, or Ru, and Au, Co, Fe, Ir, Ni, Pd , Pt, Rh, Os, or Ru is an organic ligand through a heteroatom (s) or non-carbon atom (s) (eg, oxygen, nitrogen, chalcogen (eg, sulfur and selenium), phosphorus or halide) And form a coordination bond. Exemplary Au, Co, Fe, Ir, Ni, Pd, Pt, Rh, Os or Ru complexes with organic ligands can be formed through π bonds. Examples of the organic ligand having an oxygen heteroatom include functional groups such as hydroxyl, ether, carbonyl, ester, carboxyl, aldehyde, anhydride, cyclic anhydride, and epoxy. Examples of organic ligands having nitrogen heteroatoms include amines, amides, imides, imines, azides, azines, pyrroles, pyridines, porphyrins, isocyanates, carbamates, carbamides, sulfamates, sulfamides, amino acids and N-heterocyclic carbaine. A functional group is mentioned. As organic ligands having sulfur heteroatoms, so-called thio ligands, functional groups (eg, thiol, thioketone (thione or thiocarbonyl), thiary, thiophene, disulfide, polysulfide, sulfimide, sulfoximide, and sulfoneimine) can be used. Can be mentioned. Examples of the organic ligand having a phosphorus heteroatom include functional groups (for example, phosphine, phosphane, phosphanide, and phosphinidene). Exemplary organometallic complexes include Au, Co, Fe, Ir, Ni, Pd, Pt, Rh, Os, or Ru, either a homofunctional organic ligand or a heterofunctional organic ligand. And homo- and heterobimetallic complexes involved in the coordination bond. Au, Co, Fe, Ir, Ni, Pd, Pt, Rh, Os, or Ru organometallic complexes formed through π coordination bonds include carbon-rich π-conjugated organic ligands (eg, allene, Allyl, diene, carbene and alkynyl). Examples of Au, Co, Fe, Ir, Ni, Pd, Pt, Rh, Os or Ru organometallic complexes are chelates, tweezer molecules, cages, molecular boxes, mobile molecules, macrocycles, prisms, half sandwiches And also known as the metal-organic framework (MOF). Exemplary organometallic compounds comprising at least one of Au, Co, Fe, Ir, Ni, Pd, Pt, Rh, Os or Ru include covalent bonds, ionic bonds or covalent-ionic bond mixed metals -A compound in which Au, Co, Fe, Ir, Ni, Pd, Pt, Rh, Os or Ru is bonded to an organic substance through a carbon bond. Exemplary organometallic compounds also include covalent bonds to heteroatoms (eg, oxygen, nitrogen, chalcogens (eg, sulfur) such as Au, Co, Fe, Ir, Ni, Pd, Pt, Rh, Os, or Ru. And a combination of at least two of the coordination bonds to the organic ligand via selenium, phosphorus or halide). The chemical formula of a stable organometallic complex is typically predictable from the 18 electron rule. The 18-electron rule is based on the fact that the transition metal valence shell consists of 9 valence orbitals that can accommodate a total of 18 electrons, either as bonded or unbonded electron pairs. The combination of these nine atomic orbitals and the ligand orbitals yields nine molecular orbitals that are either metal-ligand bonded or non-bonded. The 18-electron rule is generally not applicable to non-transition metal complexes. The 18-electron rule usefully predicts the chemical formula of low-spin complexes of Cr, Mn, Fe and Co trivalent elements. Well known examples include ferrocene, iron pentacarbonyl, chromium carbonyl and nickel carbonyl. The ligand in the complex determines whether the 18 electron rule is applicable. In general, complexes that follow the 18-electron rule are at least partially composed of π-acceptor ligands (also known as π acids). This type of ligand creates a very strong ligand field, thus reducing the energy of the resulting molecular orbitals and advantageously occupying the activation. Typical ligands include olefins, phosphines and CO. The π-acid complex is typically characterized by a low oxidation state metal. The relationship between the oxidation state and the nature of the ligand is explained in the framework of π donation. Exemplary carbides, carbide _Au 2 _{C 2} or other elements _{(e.g., Ni 2 C, Ni 3 C} , NiC, Fe 2 C, Fe 3 C, Fe x C y, CoC, Co 2 C, Co _{3 C, IrC, IrC 2,} IrC 4, Ir 4 C 5, Ir x C y, Ru 2 C, RuC, RhC, PtC, OsC, OsC 3 and OSC ₂₎ and the like. Exemplary fluorides include AuF, AuF ₃ , AuF ₅ , FeF ₂ , FeF ₃ , CoFe ₂ , CoF ₃ , NiF ₂ , IrF ₃ , IrF ₄ , Ir _x F _y , PdF ₃ , PdF ₄ , RhF ₃ , RhF ₄ , RhF ₆ RuF 3 and OsF ₆ . Exemplary nitrides include Au ₃ N, AuN ₂ , Au _x N _y , Ni ₃ N, NiN, Co ₂ N, CoN, Co ₂ N ₃ , Co ₄ N, Fe ₂ N, Fe ₃ N _x ( Where x = 0.75 to 1.4), Fe ₄ N, Fe ₈ N, Fe ₁₆ N ₂ , IrN, IrN ₂ , IrN ₃ , RhN, RhN ₂ , RhN ₃ , Ru ₂ N, RuN, RuN ₂ , PdN, PdN ₂ , OsN, OsN ₂ and OsN ₄ . Exemplary _{borides, Au x B y, Mn 2} AuB, Ni x B y, CoB, Co 2 B, Co 3 B, FeB, Fe 2 B, Ru 2 B 3, RuB 2, IrB, Ir x Examples include B _y , OsB, Os ₂ B ₃ , OsB ₂ , RhB and their acid borides, boron-containing nitrides, and boron-containing carbides. Exemplary acid _{carbide, Au x O y C z,} Ni x O y C z, Fe x O y C z, Co x O y C z, Ir x O y C z, Ru x O y C z, _{Rh x O y C z, Pt} x O y C z, include Pd _x O y _{C z,} and _Os x _O y _{C z.} Exemplary acid _{fluoride, Au x O y F z,} Ni x O y F z, Fe x O y F z, Co x O y F z, Ir x O y F z, Ru x O y F z Rh _x O _y F _z , Pt _x O _y F _z , Pd _x O _y F _z and Os _x O _y F _z . Exemplary _{oxynitride, Au x O y N z,} Ni x O y N z, Fe x O y N z, Co x O y N z, Ir x O y N z, Ru x O y N z , Rh _x O _y N _z , Pt _x O _y N _z , Pd _x O _y N _z and Os _x O _y N _z . It is within the scope of this disclosure to include composites containing these oxides, organometallic complexes, carbides, fluorides, nitrides, borides, oxycarbides, oxyfluorides, oxynitrides and / or oxyborides. Is within.

  In some embodiments, the anode catalyst layer or cathode catalyst layer comprises nanostructured whiskers with attached catalyst. Nanostructured whiskers are described in U.S. Pat. Nos. 4,812,352 (Debe), 5,039,561 (Debe), 5,338,430 (Parsonage et al.), 6,136,412 (Spiewak et al.), And 7,417,441 (Vernstrom et al.) The disclosures of these patents can be made by techniques well known in the art, including those described in (incorporated herein by reference). In general, nanostructured whiskers, for example, vacuum deposit (eg, by sublimation) a layer of organic or inorganic material onto a substrate (eg, a microstructured catalyst transfer polymer sheet) and then perylene red When deposited, it can be produced by converting perylene red pigment to nanostructured whiskers by thermal annealing. Typically, the vacuum deposition process is performed at a total pressure of about 10-3 TORR (0.1 Pascal) or less. Exemplary microstructures include organic pigments C.I. I. It is made by thermal sublimation and vacuum annealing of pigment red 149 (i.e., N, N'-di (3,5-xylyl) perylene-3,4: 9,10-bis (dicarboximide)). A method for producing an organic nanostructured layer is described in, for example, Materials Science and Engineering, A158 (1992), pp. 1-6; Vac. Sci. Technol. A, 5 (4), July / August 1987, pp. 196 1914-16; Vac. Sci. Technol. A, 6, (3), May / August 1988, pp. 1907-11; Thin Solid Films, 186, 1990, pp. 327-47; Mat. Sci. , 25, 1990, pp. 5257-68; Rapidly Quenched Metals, Proc. of the First Int. Conf. on Rapidly Quenched Metals, Würzburg, Germany (September 3-7, 1984), S.E. Edited by Steve et al., Elsevier Science Publishers B.M. V. , New York (1985), pp. 1117-24; Photo. Sci. and Eng. , 24, (4), July / August 1980, pp. 211-16; and U.S. Pat. Nos. 4,340,276 (Maffitt et al.) And 4,568,598 (Bilkadi et al.), The disclosures of which are incorporated herein by reference. The characteristics of the catalyst layer using the carbon nanotube array are disclosed in a paper “High Dispersion and Electrocatalytic Properties of Platinum on Well-Aligned Carbon Nanotube Arrays”, Carbon 42 (2004), 19-19. The properties of catalyst layers using grassy or brilliant silicon are disclosed, for example, in US 2004/0048466 (A1) (Gore et al.).

  The vacuum deposition may be performed in any suitable apparatus (eg, US Pat. Nos. 5,338,430 (Parsonage et al.), 5879827 (Debe et al.), 5879828 (Debe et al.), And 6040077 (Debe). And US Pat. No. 6,319,293 (Debe et al.) And US Patent Application Publication No. 2002/0004453 (A1) (Haugen et al., The disclosures of these patents are incorporated herein by reference). One exemplary device is schematically illustrated in FIG. 4A of US Pat. No. 5,338,430 (Parsonage et al.) And described in the accompanying text. Here, the substrate is mounted on a drum and then rotated on a sublimation or evaporation source to deposit an organic precursor (eg, perylene red pigment), and then an organic precursor to form a nanostructured whisker. The body is annealed.

  Typically, the nominal thickness of the deposited perylene red pigment is in the range of about 50 nm to 500 nm. Typically, whiskers have an average cross-sectional dimension in the range of 20 nm to 60 nm and an average length in the range of 0.3 micrometers to 3 micrometers.

  In some embodiments, the whiskers are attached to the backing. Exemplary backings include polyimide, nylon, metal foil, or other materials that can withstand thermal annealing temperatures up to 300 ° C. In some embodiments, the backing has an average thickness in the range of 25 micrometers to 125 micrometers.

  In some embodiments, the backing has a microstructure on at least one of its surfaces. In some embodiments, the microstructure has a substantially uniform shape that is at least 3 times the average size of nanostructured whiskers (in some embodiments, at least 4 times, 5 times, 10 times, or more). And dimensional features. The shape of the microstructure can be, for example, a V-shaped groove and top (eg, US Pat. No. 6,136,412 (Spiewak et al.), Incorporated herein by reference) or pyramid (eg, see US Pat. No. 7,901,829 (Debe et al.)), Incorporated herein by reference. In some embodiments, some of the microstructure features periodically extend above the average or most of the microstructured peak, eg, every 31 V-shaped groove peaks on either side of it. 25%, 50%, or 100% higher than the peak. In some embodiments, some of the features that extend above the majority of the microstructured peak are up to 10% (in some embodiments, up to 3%, 2%, or even up to 1 %). Occasionally, a high microstructure feature can help protect the top of the uniformly small microstructure as the coated substrate moves across the roll surface during a low-to-roll coating operation. Nanostructured materials that can be scraped off or otherwise obstructed as the substrate progresses through the coating process because the high features that appear from time to time contact the surface of the roller rather than the small microstructure peaks or Whisker material can be very low. In some embodiments, the microstructure features are substantially less than half the thickness of the membrane to which the catalyst travels during manufacture of the membrane electrode assembly. This is so that during the catalyst transfer process, high microstructure features do not penetrate the membrane which can overlap the electrodes on the opposite side of the membrane. In some embodiments, the highest microstructured feature is less than 1/3 or 1/4 of the film thickness. For thinnest ion exchange membranes (eg, about 10 to 15 micrometers thick), it is desirable to have a substrate with microstructural features that are no more than about 3 to 4.5 micrometers in height There is a case. In some embodiments, it may be desirable for the side slope of the V-shaped or other microstructured features, ie, the included angle between adjacent features, to be about 90 °, which may be useful during the stack transfer process. To increase the surface area of the electrode by making the surface area of the microstructured layer 2 square root (1.414) times the flat geometric surface of the substrate backing It is.

In some embodiments, the anode catalyst layer is
(A ′) at least one of the elements Al, carbon, Hf, Nb, Re, Si, Sn, Ta, Ti, W or Zr,
(B ′) at least one alloy comprising at least one of Al, carbon, Hf, Nb, Re, Si, Sn, Ta, Ti, W or Zr;
(C ′) at least one composite comprising at least one of Al, carbon, Hf, Nb, Re, Si, Sn, Ta, Ti, W or Zr;
(D ′) at least one oxide of at least one of Al, Hf, Nb, Re, Si, Sn, Ta, Ti, W or Zr,
(E ′) at least one organometallic complex of at least one of Al, Hf, Nb, Re, Si, Sn, Ta, Ti, W or Zr,
(F ′) at least one carbide of at least one of Al, Hf, Nb, Re, Si, Sn, Ta, Ti, W or Zr,
(G ′) at least one fluoride of at least one of Al, carbon, Hf, Nb, Re, Si, Sn, Ta, Ti, W or Zr,
(H ′) at least one nitride of at least one of Al, carbon, Hf, Nb, Re, Si, Sn, Ta, Ti, W or Zr,
(I ′) at least one oxycarbide of at least one of Al, Hf, Nb, Re, Si, Sn, Ta, Ti, W or Zr,
(J ′) at least one oxyfluoride of at least one of Al, Hf, Nb, Re, Si, Sn, Ta, Ti, W or Zr,
(K ′) at least one oxynitride of at least one of Al, carbon, Hf, Nb, Re, Si, Sn, Ta, Ti, W or Zr,
(L ′) at least one boride of at least one of Al, carbon, Hf, Nb, Re, Si, Sn, Ta, Ti, W or Zr, or (m ′) Al, Hf, Nb, Re , Si, Sn, Ta, Ti, W or Zr, including at least one of at least one acid boride (wherein oxide, organometallic complex, boron) , Carbides, fluorides, nitrides, oxyborides, oxycarbides, oxyfluorides and oxynitrides are present with Al, carbon, Hf, Nb, Re, Si, Sn, Ta, Ti, W or Zr Please understand that.

Exemplary oxides include HfO, Hf ₂ O ₃ , HfO ₂ , TaO, Ta ₂ O ₅ , SnO, SnO ₂ , TiO, Ti ₂ O ₃ , TiO ₂ , Ti _x O _y , ZrO, Zr ₂ O. ₃ , ZrO ₂ , yttria stabilized zirconia (YSZ), W ₂ O ₃ , WO ₃ , ReO ₂ , ReO ₃ , Re ₂ O ₃ , Re ₂ O ₇ , NbO, NbO ₂ , Nb ₂ O ₅ , Al ₂ O _{3, AlO,} Al 2 O, the SiO and SiO ₂ and the like. Exemplary organometallic complexes include at least one of Al, Hf, Nb, Re, Si, Sn, Ta, Ti, W, or Zr, including Al, Hf, Nb, Re, Si, Sn, Ta , Ti, W or Zr can be coordinated with the organic ligand through heteroatom (s) or non-carbon atom (s) (eg, oxygen, nitrogen, chalcogen (eg, sulfur and selenium), phosphorus or halide). To form coordinate bonds. Exemplary Al, Hf, Nb, Re, Si, Sn, Ta, Ti, W or Zr complexes with organic ligands can be formed through π bonds. Examples of the organic ligand having an oxygen heteroatom include functional groups such as hydroxyl, ether, carbonyl, ester, carboxyl, aldehyde, anhydride, cyclic anhydride, and epoxy. Examples of organic ligands having nitrogen heteroatoms include amines, amides, imides, imines, azides, azines, pyrroles, pyridines, porphyrins, isocyanates, carbamates, carbamides, sulfamates, sulfamides, amino acids and N-heterocyclic carbaine. A functional group is mentioned. As organic ligands having sulfur heteroatoms, so-called thio ligands, functional groups (eg, thiol, thioketone (thione or thiocarbonyl), thiary, thiophene, disulfide, polysulfide, sulfimide, sulfoximide, and sulfoneimine) can be used. Can be mentioned. Examples of the organic ligand having a phosphorus heteroatom include functional groups (for example, phosphine, phosphane, phosphanide, and phosphinidene). Also, as an exemplary organometallic complex, Al, Hf, Nb, Re, Si, Sn, Ta, Ti, W, or Zr may be either a homofunctional organic ligand or a heterofunctional organic ligand. And homo- and heterobimetallic complexes involved in the coordination bond. Al, Hf, Nb, Re, Si, Sn, Ta, Ti, W, or Zr organometallic complexes formed through π coordination bonds include carbon-rich π-conjugated organic ligands (eg, allene, Allyl, diene, carbene and alkynyl). Examples of Al, Hf, Nb, Re, Si, Sn, Ta, Ti, W or Zr organometallic complexes are chelates, tweezer molecules, cages, molecular boxes, mobile molecules, macrocycles, prisms, half sandwiches And also known as the metal-organic framework (MOF). Exemplary organometallic compounds containing at least one of Al, Hf, Nb, Re, Si, Sn, Ta, Ti, W or Zr include covalent bonds, ionic bonds or covalent-ionic bond mixed metals -A compound in which Al, Hf, Nb, Re, Si, Sn, Ta, Ti, W or Zr is bonded to an organic substance through a carbon bond. Exemplary organometallic compounds also include covalent bonds and heteroatoms (eg, oxygen, nitrogen, chalcogen (eg, sulfur) to carbon atoms of Al, Hf, Nb, Re, Si, Sn, Ta, Ti, W or Zr. And a combination of at least two of the coordination bonds to the organic ligand via selenium, phosphorus or halide). The chemical formula of a stable organometallic complex is typically predictable from the 18 electron rule. The 18-electron rule is based on the fact that the transition metal valence shell consists of 9 valence orbitals that can accommodate a total of 18 electrons, either as bonded or unbonded electron pairs. The combination of these nine atomic orbitals and the ligand orbitals yields nine molecular orbitals that are either metal-ligand bonded or non-bonded. The 18-electron rule is generally not applicable to non-transition metal complexes. The ligand in the complex determines whether the 18 electron rule is applicable. In general, complexes that follow the 18-electron rule are at least partially composed of π-acceptor ligands (also known as π acids). This type of ligand creates a very strong ligand field, thus reducing the energy of the resulting molecular orbitals and advantageously occupying the activation. Typical ligands include olefins, phosphines and CO. The π-acid complex is typically characterized by a low oxidation state metal. The relationship between the oxidation state and the nature of the ligand is explained in the framework of π donation. For further details, see, for example, Organometallic Chemistry of Titanium, Zirconium, and Hafnium, A volume in Organometallic Chemistry: A Series of Monographs. C. See Wales, ISBN: 978-0-12-730350-5. Exemplary carbides include HfC and HfC ₂ , Nb ₂ C, Nb ₄ C ₃ and NbC, Re ₂ C, TaC, Ta ₄ C ₃ , Ta ₂ C, WC, W ₂ C, WC ₂ , Zr ₂ C , Zr ₃ C ₂ , Zr ₆ C, TiC, Ti ₈ C ₁₂ ⁺ clusters and ternary compounds Ti—Al—C and Ti—Sn—C carbide phases (eg, Ti ₃ AlC, Ti ₃ AlC ₂ , Ti _{2 AlC, Ti 2 SnC, Al} 4 C 3, SnC, Sn 2 C , and _Al 4 _{C 3)} can be mentioned. Exemplary fluorides include ZrF ₄ , TiF ₄ , TiF ₃ , TaF ₅ , NbF ₄ , NbF ₅ , WF ₆ , AlF ₃ , HfF ₄ , CF, CF _x , (CF) _x , SnF ₂ and SnF ₄ Is mentioned. Exemplary nitrides include Hf ₃ N ₄ , HfN, Re ₂ N, Re ₃ N, ReN, Nb ₂ N, NbN, Nb carbon-containing nitride, TaN, Ta ₂ N, Ta ₅ N ₆ , Ta ₃ N ₅ , W ₂ N, WN, WN ₂ , Zr ₃ N ₄ , ZrN, β-C ₃ N ₄ , graphite-like gC ₃ N ₄ and Si ₃ N ₄ may be mentioned. Exemplary acid _{carbide, Al x O y C z,} Hf x O y C z, Zr x O y C z, Ti x O y C z, Ta x O y C z, Re x O y C z, Nb _{x O y C z, W x} O y C z and _Sn x _O y _{C z,} and the like. Exemplary acid _{fluoride, Al x O y F z,} Hf x O y F z, Zr x O y F z, Ti x O y F z, Ta x O y F z, Re x O y F z, _{nb x O y F z, W} x O y F z and _Sn x _O y _{F z,} and the like. Exemplary _{oxynitride, Al x O y N z,} Hf x O y N z, Zr x O y N z, Ti x O y N z, Ta x O y N z, Re x O y N z, _{nb x O y N z, W} x O y N z, include C _x O y _{N x} and _Sn x _O y _{F z.} Exemplary _{borides, ZrB 2, TiB 2, TaB} , Ta 5 B 6, Ta 3 B 4, TaB 2, NbB 2, NbB, WB, WB 2, AlB 2, HfB 2, ReB 2, B 4 C , SiB ₃ , SiB ₄ , SiB _{6 and} their acid borides, boron-containing nitrides and boron-containing carbides. It is within the scope of this disclosure to include composites containing these oxides, organometallic complexes, carbides, fluorides, nitrides, oxycarbides, oxyfluorides and / or oxynitrides. The composition and amount of the various components of the multi-component catalyst can affect the performance of the catalyst and the overall performance of the device using the catalyst (e.g., too much Ti in a Pt anode catalyst can reduce cell performance. )

  The catalyst and catalyst support material can be deposited by techniques well known in the art, as appropriate. Exemplary deposition methods include sputtering (including reactive sputtering), atomic layer deposition, organic molecular chemical vapor deposition, metalorganic chemical vapor deposition, molecular beam epitaxy, thermophysical vapor deposition, vacuum deposition by electrospray ionization, and And a technique selected independently from the group consisting of pulsed laser deposition. In thermal physical vapor deposition, the target (raw material) is melted or sublimed into a vapor state using an appropriate desired temperature (eg, by resistance heating, an electron beam gun or a laser), and then the vapor target is vacuumed. When passed through the space, the vapor form condenses on the substrate surface. Thermal physical vapor deposition devices are well known in the art, for example, as metal evaporators, commercially available from ClearPhys GmbH, under the trade name “METAL Evaporator” (ME-Series), or as organic material evaporators. An apparatus commercially available from Mantis Deposition LTD (Oxfordshire, UK) under the trade name "ORGANIC MATERIALS EVAPORATION (ORMA-Series)". A catalyst comprising a plurality of alternating layers may be sputtered from a plurality of targets, for example (eg, Nb is sputtered from a first target, Zr is sputtered from a second target, and Hf (if any) is third. Sputtering from a target, etc.), and sputtering from a target (s) containing two or more elements. When the coating of the catalyst is performed with a single target, the coating layer is deposited on the GDL in a single step so that the condensation heat of the catalyst coating is Al, carbon, Hf, Ta, Si, Sn, Ti, Zr or Sufficient surface movement to heat atoms such as W (if applicable) and sufficiently heat the substrate surface to form a well-mixed and thermodynamically stable alloy region It may be desirable to provide a degree. Alternatively, for example, the substrate can also be served in a heated state or heated to increase this atomic mobility. In some embodiments, sputtering is at least partially performed in an atmosphere comprising at least a mixture of argon and oxygen, and the ratio of the argon flow rate to the oxygen flow rate to the sputtering chamber is at least 113 sccm / 7 sccm. The organometallic catalyst and catalyst support material can be deposited as appropriate, for example, by soft landing or reactive landing of mass-selected ions. Soft landing of mass-selected ions is used to move catalytically active metal complexes with organic ligands from the gas phase onto an inert surface. This method can be used to prepare substances with well-defined active sites, thereby allowing surface molecular design to be performed in a highly controlled manner under ambient or conventional vacuum conditions. For further details see, for example, Johnson et al., Anal. See Chem 2010, 82, 5718-5727 and Johnson et al., Chemistry: A European Journal 2010, 16, 14433-14438, the disclosures of which are incorporated herein by reference.

In some embodiments, the cathode catalyst layer is
(A ′ ″) at least one of the elements Al, carbon, Hf, Nb, Re, Si, Sn, Ta, Ti, W or Zr,
(B ′ ″) at least one alloy comprising at least one of Al, carbon, Hf, Nb, Re, Si, Sn, Ta, Ti, W or Zr;
(C ′ ″) at least one composite comprising at least one of Al, carbon, Hf, Nb, Re, Si, Sn, Ta, Ti, W or Zr;
(D ′ ″) at least one oxide of at least one of Al, Hf, Nb, Re, Si, Sn, Ta, Ti, W or Zr,
(E ′ ″) at least one organometallic complex of at least one of Al, Hf, Nb, Re, Si, Sn, Ta, Ti, W or Zr,
(F ″ ′) at least one carbide of at least one of Al, Hf, Nb, Re, Si, Sn, Ta, Ti, W or Zr,
(G ′ ″) at least one fluoride of at least one of Al, carbon, Hf, Nb, Re, Si, Sn, Ta, Ti, W or Zr,
(H ′ ″) at least one nitride of at least one of Al, carbon, Hf, Nb, Re, Si, Sn, Ta, Ti, W or Zr,
(I ′ ″) at least one oxycarbide of at least one of Al, Hf, Nb, Re, Si, Sn, Ta, Ti, W or Zr,
(J ′ ″) at least one oxyfluoride of at least one of Al, Hf, Nb, Re, Si, Sn, Ta, Ti, W or Zr,
(K ′ ″) at least one oxynitride of at least one of Al, carbon, Hf, Nb, Re, Si, Sn, Ta, Ti, W or Zr,
(L ′ ″) at least one boride of at least one of Al, carbon, Hf, Nb, Re, Si, Sn, Ta, Ti, W or Zr, or (m ′ ″) Al, Hf , Nb, Re, Si, Sn, Ta, Ti, W or Zr, including at least one of oxyboride and at least one support material (wherein oxide, organic (It should be understood that metal complexes, borides, carbides, fluorides, nitrides, oxycarbides, oxyfluorides, oxyborides and oxynitrides are present with a ′ ″).

Exemplary oxides include HfO, Hf ₂ O ₃ , HfO ₂ , TaO, Ta ₂ O ₅ , SnO, SnO ₂ , TiO, Ti ₂ O ₃ , TiO ₂ , Ti _x O _y , ZrO, Zr ₂ O. ₃ , ZrO ₂ , yttria stabilized zirconia (YSZ), W ₂ O ₃ , WO ₃ , ReO ₂ , ReO ₃ , Re ₂ O ₃ , Re ₂ O ₇ , NbO, NbO ₂ , Nb ₂ O ₅ , Al ₂ O _{3, AlO,} Al 2 O, the SiO and SiO ₂ and the like. Exemplary organometallic complexes include at least one of Al, Hf, Nb, Re, Si, Sn, Ta, Ti, W, or Zr, including Al, Hf, Nb, Re, Si, Sn, Ta , Ti, W or Zr can be coordinated with the organic ligand through heteroatom (s) or non-carbon atom (s) (eg, oxygen, nitrogen, chalcogen (eg, sulfur and selenium), phosphorus or halide). To form coordinate bonds. Exemplary Al, Hf, Nb, Re, Si, Sn, Ta, Ti, W or Zr complexes with organic ligands can be formed through π bonds. Examples of the organic ligand having an oxygen heteroatom include functional groups such as hydroxyl, ether, carbonyl, ester, carboxyl, aldehyde, anhydride, cyclic anhydride, and epoxy. Examples of organic ligands having nitrogen heteroatoms include amines, amides, imides, imines, azides, azines, pyrroles, pyridines, porphyrins, isocyanates, carbamates, carbamides, sulfamates, sulfamides, amino acids and N-heterocyclic carbaine. A functional group is mentioned. As organic ligands having sulfur heteroatoms, so-called thio ligands, functional groups (eg, thiol, thioketone (thione or thiocarbonyl), thiary, thiophene, disulfide, polysulfide, sulfimide, sulfoximide, and sulfoneimine) can be used. Can be mentioned. Examples of the organic ligand having a phosphorus heteroatom include functional groups (for example, phosphine, phosphane, phosphanide, and phosphinidene). Also, as an exemplary organometallic complex, Al, Hf, Nb, Re, Si, Sn, Ta, Ti, W, or Zr may be either a homofunctional organic ligand or a heterofunctional organic ligand. And homo- and heterobimetallic complexes involved in the coordination bond. Al, Hf, Nb, Re, Si, Sn, Ta, Ti, W, or Zr organometallic complexes formed through π coordination bonds include carbon-rich π-conjugated organic ligands (eg, allene, Allyl, diene, carbene and alkynyl). Examples of Al, Hf, Nb, Re, Si, Sn, Ta, Ti, W or Zr organometallic complexes are chelates, tweezer molecules, cages, molecular boxes, mobile molecules, macrocycles, prisms, half sandwiches And also known as the metal-organic framework (MOF). Exemplary organometallic compounds containing at least one of Al, Hf, Nb, Re, Si, Sn, Ta, Ti, W or Zr include covalent bonds, ionic bonds or covalent-ionic bond mixed metals -A compound in which Al, Hf, Nb, Re, Si, Sn, Ta, Ti, W or Zr is bonded to an organic substance through a carbon bond. Exemplary organometallic compounds also include covalent bonds and heteroatoms (eg, oxygen, nitrogen, chalcogen (eg, sulfur) to carbon atoms of Al, Hf, Nb, Re, Si, Sn, Ta, Ti, W or Zr. And a combination of at least two of the coordination bonds to the organic ligand via selenium, phosphorus or halide). The chemical formula of a stable organometallic complex is typically predictable from the 18 electron rule. The 18-electron rule is based on the fact that the transition metal valence shell consists of 9 valence orbitals that can accommodate a total of 18 electrons, either as bonded or unbonded electron pairs. The combination of these nine atomic orbitals and the ligand orbitals yields nine molecular orbitals that are either metal-ligand bonded or non-bonded. The 18-electron rule is generally not applicable to non-transition metal complexes. The ligand in the complex determines whether the 18 electron rule is applicable. In general, complexes that follow the 18-electron rule are at least partially composed of π-acceptor ligands (also known as π acids). This type of ligand creates a very strong ligand field, thus reducing the energy of the resulting molecular orbitals and advantageously occupying the activation. Typical ligands include olefins, phosphines and CO. The π-acid complex is typically characterized by a low oxidation state metal. The relationship between the oxidation state and the nature of the ligand is explained in the framework of π donation. For further details, see, for example, Organometallic Chemistry of Titanium, Zirconium, and Hafnium, A volume in Organometallic Chemistry: A Series of Monographs. C. See Wales, ISBN: 978-0-12-730350-5. Exemplary carbides include HfC, HfC ₂ , Nb ₂ C, Nb ₄ C ₃ , NbC, Re ₂ C, TaC, Ta ₄ C ₃ , Ta ₂ C, WC, W ₂ C, WC ₂ , Zr ₂ C , Zr ₃ C ₂ , Zr ₆ C, TiC, Ti ₈ C ₁₂ ⁺ clusters and carbide phases that are ternary compounds (eg, Ti ₃ AlC, Ti ₃ AlC ₂ , Ti ₂ AlC, Ti ₂ SnC, Al ₄ C ₃ , SnC, Sn ₂ C and Al ₄ C ₃ ). Exemplary fluorides include ZrF ₄ , TiF ₄ , TiF ₃ , TaF ₅ , NbF ₄ , NbF ₅ , WF ₆ , AlF ₃ , HfF ₄ , CF, CF _x , (CF) _x , SnF ₂ and SnF ₄ Is mentioned. Exemplary nitrides include Hf ₃ N ₄ , HfN, Re ₂ N, Re ₃ N, ReN, Nb ₂ N, NbN, Nb carbon-containing nitride, TaN, Ta ₂ N, Ta ₅ N ₆ , Ta ₃ N ₅ , W ₂ N, WN, WN ₂ , β-C ₃ N ₄ , graphitic g-C ₃ N ₄ , Zr ₃ N ₄ and ZrN can be mentioned. Exemplary acid _{carbide, Al x O y C z,} Hf x O y C z, Zr x O y C z, Ti x O y C z, Ta x O y C z, Re x O y C z, Nb _{x O y C z, W x} O y C z and _Sn x _O y _{C z,} and the like. Exemplary acid _{fluoride, Al x O y F z,} Hf x O y F z, Zr x O y F z, Ti x O y F z, Ta x O y F z, Re x O y F z, _{nb x O y F z, W} x O y F z and _Sn x _O y _{F z,} and the like. Exemplary _{oxynitride, Al x O y N z,} Hf x O y N z, Zr x O y N z, Ti x O y N z, Ta x O y N z, Re x O y N z, _{nb x O y N z, W} x O y N z and _Sn x _O y _{F z,} and the like. Exemplary borides include ZrB ₂ , TiB ₂ , TaB, Ta ₅ B ₆ , Ta ₃ B ₄ , TaB ₂ , NbB ₂ , NbB, WB, WB ₂ , AlB ₂ , HfB ₂ , ReB ₂ , C ₄ B , SiB ₃ , SiB ₄ , SiB ₆ and their boron-containing nitrides and boron-containing carbides. It is within the scope of this disclosure to include composites containing these oxides, organometallic complexes, carbides, fluorides, nitrides, oxycarbides, oxyfluorides and / or oxynitrides.

  The method of providing or incorporating the catalyst and catalyst support layer in the GDL can also be based on the liquid phase. Suitable coating methods include suspension, electrophoresis or electrochemical deposition and impregnation. For example, if the gas dispersion layer can be deposited on the gas supply layer based on the slurry, the slurry can contain catalyst particles along with carbon particles and a fluoropolymer binder. For further details, see, for example, Applied Catalysis A: General, 315, 2006, 1-17, a report by Valerie Maille, the disclosure of which is incorporated herein by reference.

  In this specification, including the presence, absence or size of one or various types of alloys, amorphous regions, crystalline regions, especially when more than two elements are combined It is understood by those skilled in the art that the crystal structure and morphological structure of the described catalyst can be highly dependent on process and manufacturing conditions.

  In some embodiments, the first layer of catalyst is deposited directly on the nanostructured whiskers. In some embodiments, the first layer is bonded to the nanostructured whisker with at least one of a covalent bond or an ionic bond. In some embodiments, the first layer is adsorbed onto the nanostructured whiskers. The first layer can be formed, for example, as a uniform conformal coating or dispersed discrete nanoparticles. Dispersed, discrete, matched nanoparticles can be formed, for example, by cluster beam deposition by controlling the pressure of the helium carrier gas or by self-assembly. For further details, see, for example, Wan et al., Solid State Communications, 121, 2002, 251-256 or Bruno Chaudret's Top Organome Chem, 2005, 16, 233-259, the disclosures of which are incorporated herein by reference. Is incorporated herein by reference.

In some embodiments, at least one of the following conditions is met:
(A) at least one of the plurality of layers comprising the oxygen evolution reaction catalyst is 1: 1 or less (in some embodiments, 0.9: 1 or less, 0.8: 1 or less, 0.75: 1 0.7: 1 or less, 0.6: 1 or less, 0.5: 1 or less, 0.4: 1 or less, 0.3: 1 or less, 0.25: 1 or less, 0.2: 1 or less Or the ratio of the elemental metal Pt to the elemental metal oxygen evolution reaction catalyst of 0.1: 1 or less (or even 0: 1 or less) (ie, RuO ₂ is an oxygen evolution reaction catalyst, Ru (A ratio of the number of Pt atoms to the number of atoms), or (b) a first gas supply layer, a second gas supply layer, an optional first gas dispersion layer or an optional oxygen generation reaction catalyst At least one of the layers disposed on at least one of the second gas dispersion layers is 1: 1 or less ( In some embodiments, 0.9: 1 or less, 0.8: 1 or less, 0.75: 1 or less, 0.7: 1 or less, 0.6: 1 or less, 0.5: 1 or less, 0 .4: 1 or less, 0.3: 1 or less, 0.25: 1 or less, 0.2: 1 or less, or 0.1: 1 or less, or even 0: 1 or less) It has the ratio of elemental metal Pt to the metal oxygen evolution reaction catalyst.

The membrane electrode assembly of the present disclosure has at least one of the following (ie, any one of the following and any combination thereof, where any first and second gas dispersion layers): It is understood that reference to any first and second gas dispersion layers is intended)
A layer comprising (eg, at least partially) an oxygen evolution reaction catalyst disposed (eg, attached) on a first major surface of the first gas supply layer;
A first gas supply layer comprising an oxygen evolution reaction catalyst (eg, at least partially present, including distribution throughout the layer);
An oxygen generating reaction catalyst is disposed (eg, attached) on (eg, attached to) the second major surface of the first gas supply layer (eg, at least a portion is present, which can reduce distribution throughout the layer). Including) layer,
A layer comprising an oxygen evolution reaction catalyst (eg, at least partially present, including distribution throughout the layer) disposed between the first gas supply layer and the first gas dispersion layer;
An oxygen generating reaction catalyst is disposed (eg, attached) on (eg, attached to) the first major surface of the first gas dispersion layer (eg, there is at least a portion of this that distributes throughout the layer). Including) layer,
A first gas dispersion layer that includes an oxygen evolution reaction catalyst (eg, at least a portion is present, including distribution throughout the layer);
Comprising (eg, attached) an oxygen evolution reaction catalyst disposed (eg, attached) on the second major surface of the first gas dispersion layer (eg, there is at least a portion of this that distributes throughout the layer) Including) layer,
An oxygen generating reaction catalyst is disposed (eg, attached) on (eg, attached to) the first major surface of the second gas dispersion layer (eg, there is at least a portion of this that distributes throughout the layer). Including) layer,
A second gas dispersion layer comprising an oxygen evolution reaction catalyst (eg, at least a portion is present, including distribution throughout the layer);
Comprising (eg, attached) an oxygen generating reaction catalyst disposed (eg, attached) on the second major surface of the second gas dispersion layer (eg, there is at least a portion of this that distributes throughout the layer) Including) layer,
A layer comprising an oxygen evolution reaction catalyst (eg, at least a portion present, including distribution throughout the layer) disposed between the second gas supply layer and the second gas dispersion layer;
An oxygen generating reaction catalyst is disposed (eg, attached) on (eg, attached to) the first major surface of the second gas supply layer (eg, there is at least a portion of this that distributes throughout the layer). Including) layer,
A second gas supply layer comprising an oxygen evolution reaction catalyst (eg, at least a portion present, including distribution throughout the layer);
An oxygen generating reaction catalyst is disposed (eg, attached) on (eg, attached to) the second major surface of the second gas supply layer (eg, there is at least a portion of this that distributes throughout the layer). Including) at least one of the layers,
The amount of moiety present is at least 0.5 microgram / cm ² , and in some embodiments 1 microgram / cm ² , 1.5 microgram / cm ² , 2 microgram / cm ² , 2 0.5 microgram / cm ² , 3 microgram / cm ^2, or at least 5 microgram / cm ² , and in some embodiments within the range of 0.5 microgram / cm ^{2 to} 100 microgram / cm ² , In the range of 0.5 microgram / cm ² to 75 microgram / cm ² , in the range of 0.5 microgram / cm ² to 50 microgram / cm ² , 0.5 microgram / cm ^{2 to} 25 micro in the range of grams / cm ^2, 1 microgram ^/ cm 2 to 100 micrograms / cm in the range of ^2, 1 microgram / cm In the range of 75 micrograms / cm ^2, 1 microgram ^/ cm 2 to 50 in the range of micrograms / cm ^2, 1 microgram ^/ cm 2 to 25 in the range of micrograms / cm ^2, 2 microgram / cm Within the range of ^{2 to} 100 microgram / cm ² , within the range of 2 microgram / cm ² to 75 microgram / cm ² , within the range of 2 microgram / cm ² to 50 microgram / cm ² , 2 microgram / in the range of cm ² to 30 microgram / cm ^{2, in} the range of 2 microgram / cm ^{2 to} 25 microgram / cm ² , or in the range of 2 microgram / cm ^{2 to} 20 microgram / cm ² , which Is based on the elemental metal content of the oxygen evolution reaction catalyst.

In some embodiments, at least the first gas supply layer and / or the second gas supply layer, if present, is substantially free of Pt (ie, less than 0.1 microgram / cm ² of Pt). Is).

  Unexpectedly, an oxygen evolution reaction (OER) catalyst (eg, Ru, Ir, RuIr or an oxide thereof) and a Pt-based hydrogen oxidation reaction (HOR) catalyst on the anode side of a hydrogen PEM fuel cell or Pt on the cathode side The physical durability of the catalyst in relation to gas switching events such as start / stop or cell reversal (due to local fuel depletion) by physically separating it from the system oxygen reduction reaction (ORR) catalyst Has been found to achieve a dramatic improvement. A further advantage of the membrane electrode assembly (MEA) described herein is that the oxygen evolution reaction catalyst can be varied independently of the selection of the anode and cathode catalyst layers to be joined to the polymer electrolyte membrane. Thus, the OER catalyst can be used with an electrolyte membrane with a catalyst layer having various HOR catalyst layers and ORR catalyst layers such as Pt on carbon or Pt on a nanostructured thin film support. OER catalyst loading, processing and performance enhancement aids can be tailored to meet specific customer needs such as specific anode, cathode, loading requirements, and the like. This technique also includes various electrolyte membranes with a catalyst layer (CCM) in which the OER catalyst on the gas supply layer or the gas dispersion layer or in the gas supply layer or the gas dispersion layer is one component and another catalyst layer is added thereto. ) And MEA configuration.

  The membrane electrode assemblies described herein are useful, for example, in electrochemical devices (eg, fuel cells).

Referring to FIG. 2, the fuel cell 2000 includes a first gas diffusion layer (GDL) 2103 adjacent to the anode catalyst layer 2300. The first GDL 2103 comprises at least the first gas supply layer 100 of FIG. 1 and, optionally, at least one of the elements 101, 102, 200, 201, 202, 1100, 1150, 1200, 1250 or 1300 of FIG. One is further provided. The adjacent anode catalyst layer 2300 is also adjacent to the electrolyte membrane 2400 on the side opposite to the GDL 2103. A cathode catalyst layer 2500 is adjacent to the electrolyte membrane 2400, and a second gas diffusion layer 2703 is adjacent to the cathode catalyst layer 2500. The second GDL 2703 comprises at least the second gas supply layer 700 of FIG. 1 and, optionally, of the elements 600, 601, 602, 701, 702, 1400, 1500, 1550, 1600 or 1700 of FIG. At least one of the following. GDLs 2103 and 2703 are sometimes referred to as diffusers / current collectors (DCC) or fluid transport layers (FTL). In operation, hydrogen fuel is injected into the anode portion of the fuel cell 2000 and is spread throughout the anode catalyst layer 2300 through the first gas diffusion layer 2103. In the anode catalyst layer 2300, the hydrogen fuel is divided into hydrogen ions (H ⁺ ) and electrons (e ⁻ ).

  The electrolyte membrane 2400 allows only hydrogen ions, that is, protons, to pass through the electrolyte membrane 2400 and reach the cathode portion of the fuel cell 2000. Electrons cannot pass through the electrolyte membrane 2400, but can instead flow through the external electrical circuit in the form of current. This current can, for example, supply power to an electrical load 2800, such as an electric motor, or can be directed to an energy storage device, such as a rechargeable battery.

Oxygen flows into the cathode side of the fuel cell 2000 through the second gas diffusion layer 2703. When oxygen passes through the cathode catalyst layer 2500, oxygen, protons, and electrons are combined to generate water and heat. In some embodiments, the fuel cell catalyst in the anode catalyst layer or the cathode catalyst layer or in both the anode catalyst layer and the cathode catalyst layer does not include a conductive carbonaceous material (ie, the catalyst layer is, for example, perylene. Red, fluoropolymer or polyolefin).
Exemplary Embodiment
1.
A first gas supply layer (eg, a first gas diffusion layer);
Optionally a first gas dispersion layer (eg, a first microporous layer);
An anode catalyst layer comprising a first catalyst;
A membrane,
A cathode catalyst layer comprising a second catalyst;
Optionally a second gas dispersion layer (eg, a second microporous layer);
A second gas supply layer (for example, a second gas diffusion layer) in order,
The first gas supply layer has a first main surface and a second main surface that are substantially opposed to each other,
The anode catalyst layer has a first main surface and a second main surface that are substantially opposed to each other, and the second main surface of the first gas supply layer is more anode catalyst than the second main surface of the first anode catalyst layer. Closer to the first major surface of the layer,
The membrane has a first major surface and a second major surface that are substantially opposed, wherein the second major surface of the anode catalyst layer is closer to the first major surface of the membrane than the second major surface of the membrane;
The cathode catalyst layer has a first main surface and a second main surface substantially opposed to each other, and the second main surface of the membrane is closer to the first main surface of the cathode catalyst layer than to the second main surface of the cathode catalyst layer. ,
The second gas supply layer has a first main surface and a second main surface that are substantially opposed to each other, and the second main surface of the cathode catalyst layer is also second than the second main surface of the second gas supply layer. Closer to the first main surface of the gas supply layer of
At least one of the following is present (i.e. having any one of the following and any combination, where any of the first and second gas dispersion layers are present): It should be understood that reference to any first and second gas dispersion layers is intended)
A layer comprising an oxygen evolution reaction catalyst (eg, attached) disposed over (eg, attached to) the first major surface of the first gas supply layer (eg, the amount of portion present is at least 0.5 microgram / cm). ² And in some embodiments, 1 microgram / cm ² 1.5 microgram / cm ² 2 microgram / cm ² 2.5 microgram / cm ² 3 microgram / cm ² Or at least 5 micrograms / cm ² And in some embodiments, 0.5 microgram / cm ² ~ 100 microgram / cm ² Within the range of 0.5 microgram / cm ² ~ 75 micrograms / cm ² Within the range of 0.5 microgram / cm ² ~ 50 microgram / cm ² Within the range of 0.5 microgram / cm ² ~ 25 microgram / cm ² Within the range of 1 microgram / cm ² ~ 100 microgram / cm ² Within the range of 1 microgram / cm ² ~ 75 micrograms / cm ² Within the range of 1 microgram / cm ² ~ 50 microgram / cm ² Within the range of 1 microgram / cm ² ~ 25 microgram / cm ² Within the range of 2 micrograms / cm ² ~ 100 microgram / cm ² Within the range of 2 micrograms / cm ² ~ 75 micrograms / cm ² Within the range of 2 micrograms / cm ² ~ 50 microgram / cm ² Within the range of 2 micrograms / cm ² ~ 30 microgram / cm ² Within the range of 2 micrograms / cm ² ~ 25 microgram / cm ² Or within 2 micrograms / cm ² ~ 20 microgram / cm ² Which is based on the elemental metal content of the oxygen evolution reaction catalyst),
A first gas supply layer comprising an oxygen evolution reaction catalyst (eg, the amount of portion present is at least 0.5 microgram / cm ² And in some embodiments, 1 microgram / cm ² 1.5 microgram / cm ² 2 microgram / cm ² 2.5 microgram / cm ² 3 microgram / cm ² Or at least 5 micrograms / cm ² And in some embodiments, 0.5 microgram / cm ² ~ 100 microgram / cm ² Within the range of 0.5 microgram / cm ² ~ 75 micrograms / cm ² Within the range of 0.5 microgram / cm ² ~ 50 microgram / cm ² Within the range of 0.5 microgram / cm ² ~ 25 microgram / cm ² Within the range of 1 microgram / cm ² ~ 100 microgram / cm ² Within the range of 1 microgram / cm ² ~ 75 micrograms / cm ² Within the range of 1 microgram / cm ² ~ 50 microgram / cm ² Within the range of 1 microgram / cm ² ~ 25 microgram / cm ² Within the range of 2 micrograms / cm ² ~ 100 microgram / cm ² Within the range of 2 micrograms / cm ² ~ 75 micrograms / cm ² Within the range of 2 micrograms / cm ² ~ 50 microgram / cm ² Within the range of 2 micrograms / cm ² ~ 30 microgram / cm ² Within the range of 2 micrograms / cm ² ~ 25 microgram / cm ² Or within 2 micrograms / cm ² ~ 20 microgram / cm ² Which is based on the elemental metal content of the oxygen evolution reaction catalyst),
A layer comprising an oxygen generating reaction catalyst (eg, attached) disposed over (eg, attached to) the second major surface of the first gas supply layer (eg, the amount of portion present is at least 0.5 microgram / cm). ² And in some embodiments, 1 microgram / cm ² 1.5 microgram / cm ² 2 microgram / cm ² 2.5 microgram / cm ² 3 microgram / cm ² Or at least 5 micrograms / cm ² And in some embodiments, 0.5 microgram / cm ² ~ 100 microgram / cm ² Within the range of 0.5 microgram / cm ² ~ 75 micrograms / cm ² Within the range of 0.5 microgram / cm ² ~ 50 microgram / cm ² Within the range of 0.5 microgram / cm ² ~ 25 microgram / cm ² Within the range of 1 microgram / cm ² ~ 100 microgram / cm ² Within the range of 1 microgram / cm ² ~ 75 micrograms / cm ² Within the range of 1 microgram / cm ² ~ 50 microgram / cm ² Within the range of 1 microgram / cm ² ~ 25 microgram / cm ² Within the range of 2 micrograms / cm ² ~ 100 microgram / cm ² Within the range of 2 micrograms / cm ² ~ 75 micrograms / cm ² Within the range of 2 micrograms / cm ² ~ 50 microgram / cm ² Within the range of 2 micrograms / cm ² ~ 30 microgram / cm ² Within the range of 2 micrograms / cm ² ~ 25 microgram / cm ² Or within 2 micrograms / cm ² ~ 20 microgram / cm ² Which is based on the elemental metal content of the oxygen evolution reaction catalyst),
A layer containing an oxygen evolution reaction catalyst (eg, the amount of portion present is at least 0.5 microgram / cm) disposed between the first gas supply layer and the first gas dispersion layer. ² And in some embodiments, 1 microgram / cm ² 1.5 microgram / cm ² 2 microgram / cm ² 2.5 microgram / cm ² 3 microgram / cm ² Or at least 5 micrograms / cm ² And in some embodiments, 0.5 microgram / cm ² ~ 100 microgram / cm ² Within the range of 0.5 microgram / cm ² ~ 75 micrograms / cm ² Within the range of 0.5 microgram / cm ² ~ 50 microgram / cm ² Within the range of 0.5 microgram / cm ² ~ 25 microgram / cm ² Within the range of 1 microgram / cm ² ~ 100 microgram / cm ² Within the range of 1 microgram / cm ² ~ 75 micrograms / cm ² Within the range of 1 microgram / cm ² ~ 50 microgram / cm ² Within the range of 1 microgram / cm ² ~ 25 microgram / cm ² Within the range of 2 micrograms / cm ² ~ 100 microgram / cm ² Within the range of 2 micrograms / cm ² ~ 75 micrograms / cm ² Within the range of 2 micrograms / cm ² ~ 50 microgram / cm ² Within the range of 2 micrograms / cm ² ~ 30 microgram / cm ² Within the range of 2 micrograms / cm ² ~ 25 microgram / cm ² Or within 2 micrograms / cm ² ~ 20 microgram / cm ² Which is based on the elemental metal content of the oxygen evolution reaction catalyst),
A layer comprising an oxygen evolution reaction catalyst (eg, attached) disposed over (eg, attached to) the first major surface of the first gas dispersion layer (eg, the amount of portion present is at least 0.5 microgram / cm). ² And in some embodiments, 1 microgram / cm ² 1.5 microgram / cm ² 2 microgram / cm ² 2.5 microgram / cm ² 3 microgram / cm ² Or at least 5 micrograms / cm ² And in some embodiments, 0.5 microgram / cm ² ~ 100 microgram / cm ² Within the range of 0.5 microgram / cm ² ~ 75 micrograms / cm ² Within the range of 0.5 microgram / cm ² ~ 50 microgram / cm ² Within the range of 0.5 microgram / cm ² ~ 25 microgram / cm ² Within the range of 1 microgram / cm ² ~ 100 microgram / cm ² Within the range of 1 microgram / cm ² ~ 75 micrograms / cm ² Within the range of 1 microgram / cm ² ~ 50 microgram / cm ² Within the range of 1 microgram / cm ² ~ 25 microgram / cm ² Within the range of 2 micrograms / cm ² ~ 100 microgram / cm ² Within the range of 2 micrograms / cm ² ~ 75 micrograms / cm ² Within the range of 2 micrograms / cm ² ~ 50 microgram / cm ² Within the range of 2 micrograms / cm ² ~ 30 microgram / cm ² Within the range of 2 micrograms / cm ² ~ 25 microgram / cm ² Or within 2 micrograms / cm ² ~ 20 microgram / cm ² Which is based on the elemental metal content of the oxygen evolution reaction catalyst),
A first gas dispersion layer comprising an oxygen evolution reaction catalyst (eg, the amount of portion present is at least 0.5 microgram / cm ² And in some embodiments, 1 microgram / cm ² 1.5 microgram / cm ² 2 microgram / cm ² 2.5 microgram / cm ² 3 microgram / cm ² Or at least 5 micrograms / cm ² And in some embodiments, 0.5 microgram / cm ² ~ 100 microgram / cm ² Within the range of 0.5 microgram / cm ² ~ 75 micrograms / cm ² Within the range of 0.5 microgram / cm ² ~ 50 microgram / cm ² Within the range of 0.5 microgram / cm ² ~ 25 microgram / cm ² Within the range of 1 microgram / cm ² ~ 100 microgram / cm ² Within the range of 1 microgram / cm ² ~ 75 micrograms / cm ² Within the range of 1 microgram / cm ² ~ 50 microgram / cm ² Within the range of 1 microgram / cm ² ~ 25 microgram / cm ² Within the range of 2 micrograms / cm ² ~ 100 microgram / cm ² Within the range of 2 micrograms / cm ² ~ 75 micrograms / cm ² Within the range of 2 micrograms / cm ² ~ 50 microgram / cm ² Within the range of 2 micrograms / cm ² ~ 30 microgram / cm ² Within the range of 2 micrograms / cm ² ~ 25 microgram / cm ² Or within 2 micrograms / cm ² ~ 20 microgram / cm ² Which is based on the elemental metal content of the oxygen evolution reaction catalyst),
A layer comprising an oxygen evolution reaction catalyst (eg, attached) disposed over (eg, attached to) the second major surface of the first gas dispersion layer (eg, the amount of portion present is at least 0.5 microgram / cm). ² And in some embodiments, 1 microgram / cm ² 1.5 microgram / cm ² 2 microgram / cm ² 2.5 microgram / cm ² 3 microgram / cm ² Or at least 5 micrograms / cm ² And in some embodiments, 0.5 microgram / cm ² ~ 100 microgram / cm ² Within the range of 0.5 microgram / cm ² ~ 75 micrograms / cm ² Within the range of 0.5 microgram / cm ² ~ 50 microgram / cm ² Within the range of 0.5 microgram / cm ² ~ 25 microgram / cm ² Within the range of 1 microgram / cm ² ~ 100 microgram / cm ² Within the range of 1 microgram / cm ² ~ 75 micrograms / cm ² Within the range of 1 microgram / cm ² ~ 50 microgram / cm ² Within the range of 1 microgram / cm ² ~ 25 microgram / cm ² Within the range of 2 micrograms / cm ² ~ 100 microgram / cm ² Within the range of 2 micrograms / cm ² ~ 75 micrograms / cm ² Within the range of 2 micrograms / cm ² ~ 50 microgram / cm ² Within the range of 2 micrograms / cm ² ~ 30 microgram / cm ² Within the range of 2 micrograms / cm ² ~ 25 microgram / cm ² Or within 2 micrograms / cm ² ~ 20 microgram / cm ² Which is based on the elemental metal content of the oxygen evolution reaction catalyst),
A layer comprising an oxygen evolution reaction catalyst (eg, attached) disposed over (eg, attached to) the first major surface of the second gas dispersion layer (eg, the amount of portion present is at least 0.5 microgram / cm). ² And in some embodiments, 1 microgram / cm ² 1.5 microgram / cm ² 2 microgram / cm ² 2.5 microgram / cm ² 3 microgram / cm ² Or at least 5 micrograms / cm ² And in some embodiments, 0.5 microgram / cm ² ~ 100 microgram / cm ² Within the range of 0.5 microgram / cm ² ~ 75 micrograms / cm ² Within the range of 0.5 microgram / cm ² ~ 50 microgram / cm ² Within the range of 0.5 microgram / cm ² ~ 25 microgram / cm ² Within the range of 1 microgram / cm ² ~ 100 microgram / cm ² Within the range of 1 microgram / cm ² ~ 75 micrograms / cm ² Within the range of 1 microgram / cm ² ~ 50 microgram / cm ² Within the range of 1 microgram / cm ² ~ 25 microgram / cm ² Within the range of 2 micrograms / cm ² ~ 100 microgram / cm ² Within the range of 2 micrograms / cm ² ~ 75 micrograms / cm ² Within the range of 2 micrograms / cm ² ~ 50 microgram / cm ² Within the range of 2 micrograms / cm ² ~ 30 microgram / cm ² Within the range of 2 micrograms / cm ² ~ 25 microgram / cm ² Or within 2 micrograms / cm ² ~ 20 microgram / cm ² Which is based on the elemental metal content of the oxygen evolution reaction catalyst),
A second gas dispersion layer comprising an oxygen evolution reaction catalyst (eg, the amount of portion present is at least 0.5 microgram / cm). ² And in some embodiments, 1 microgram / cm ² 1.5 microgram / cm ² 2 microgram / cm ² 2.5 microgram / cm ² 3 microgram / cm ² Or at least 5 micrograms / cm ² And in some embodiments, 0.5 microgram / cm ² ~ 100 microgram / cm ² Within the range of 0.5 microgram / cm ² ~ 75 micrograms / cm ² Within the range of 0.5 microgram / cm ² ~ 50 microgram / cm ² Within the range of 0.5 microgram / cm ² ~ 25 microgram / cm ² Within the range of 1 microgram / cm ² ~ 100 microgram / cm ² Within the range of 1 microgram / cm ² ~ 75 micrograms / cm ² Within the range of 1 microgram / cm ² ~ 50 microgram / cm ² Within the range of 1 microgram / cm ² ~ 25 microgram / cm ² Within the range of 2 micrograms / cm ² ~ 100 microgram / cm ² Within the range of 2 micrograms / cm ² ~ 75 micrograms / cm ² Within the range of 2 micrograms / cm ² ~ 50 microgram / cm ² Within the range of 2 micrograms / cm ² ~ 30 microgram / cm ² Within the range of 2 micrograms / cm ² ~ 25 microgram / cm ² Or within 2 micrograms / cm ² ~ 20 microgram / cm ² Which is based on the elemental metal content of the oxygen evolution reaction catalyst),
A layer comprising an oxygen evolution reaction catalyst (eg, attached) disposed over (eg, attached to) the second major surface of the second gas dispersion layer (eg, the amount of portion present is at least 0.5 microgram / cm). ² And in some embodiments, 1 microgram / cm ² 1.5 microgram / cm ² 2 microgram / cm ² 2.5 microgram / cm ² 3 microgram / cm ² Or at least 5 micrograms / cm ² And in some embodiments, 0.5 microgram / cm ² ~ 100 microgram / cm ² Within the range of 0.5 microgram / cm ² ~ 75 micrograms / cm ² Within the range of 0.5 microgram / cm ² ~ 50 microgram / cm ² Within the range of 0.5 microgram / cm ² ~ 25 microgram / cm ² Within the range of 1 microgram / cm ² ~ 100 microgram / cm ² Within the range of 1 microgram / cm ² ~ 75 micrograms / cm ² Within the range of 1 microgram / cm ² ~ 50 microgram / cm ² Within the range of 1 microgram / cm ² ~ 25 microgram / cm ² Within the range of 2 micrograms / cm ² ~ 100 microgram / cm ² Within the range of 2 micrograms / cm ² ~ 75 micrograms / cm ² Within the range of 2 micrograms / cm ² ~ 50 microgram / cm ² Within the range of 2 micrograms / cm ² ~ 30 microgram / cm ² Within the range of 2 micrograms / cm ² ~ 25 microgram / cm ² Or within 2 micrograms / cm ² ~ 20 microgram / cm ² Which is based on the elemental metal content of the oxygen evolution reaction catalyst),
A layer comprising an oxygen evolution reaction catalyst (eg, the portion present is at least 0.5 microgram / cm) disposed between the second gas supply layer and the second gas dispersion layer. ² And in some embodiments, 1 microgram / cm ² 1.5 microgram / cm ² 2 microgram / cm ² 2.5 microgram / cm ² 3 microgram / cm ² Or at least 5 micrograms / cm ² And in some embodiments, 0.5 microgram / cm ² ~ 100 microgram / cm ² Within the range of 0.5 microgram / cm ² ~ 75 micrograms / cm ² Within the range of 0.5 microgram / cm ² ~ 50 microgram / cm ² Within the range of 0.5 microgram / cm ² ~ 25 microgram / cm ² Within the range of 1 microgram / cm ² ~ 100 microgram / cm ² Within the range of 1 microgram / cm ² ~ 75 micrograms / cm ² Within the range of 1 microgram / cm ² ~ 50 microgram / cm ² Within the range of 1 microgram / cm ² ~ 25 microgram / cm ² Within the range of 2 micrograms / cm ² ~ 100 microgram / cm ² Within the range of 2 micrograms / cm ² ~ 75 micrograms / cm ² Within the range of 2 micrograms / cm ² ~ 50 microgram / cm ² Within the range of 2 micrograms / cm ² ~ 30 microgram / cm ² Within the range of 2 micrograms / cm ² ~ 25 microgram / cm ² Or within 2 micrograms / cm ² ~ 20 microgram / cm ² Which is based on the elemental metal content of the oxygen evolution reaction catalyst),
A layer comprising an oxygen evolution reaction catalyst (eg, attached) disposed over (eg, attached to) the first major surface of the second gas dispersion layer (eg, the amount of portion present is at least 0.5 microgram / cm). ² And in some embodiments, 1 microgram / cm ² 1.5 microgram / cm ² 2 microgram / cm ² 2.5 microgram / cm ² 3 microgram / cm ² Or at least 5 micrograms / cm ² And in some embodiments, 0.5 microgram / cm ² ~ 100 microgram / cm ² Within the range of 0.5 microgram / cm ² ~ 75 micrograms / cm ² Within the range of 0.5 microgram / cm ² ~ 50 microgram / cm ² Within the range of 0.5 microgram / cm ² ~ 25 microgram / cm ² Within the range of 1 microgram / cm ² ~ 100 microgram / cm ² Within the range of 1 microgram / cm ² ~ 75 micrograms / cm ² Within the range of 1 microgram / cm ² ~ 50 microgram / cm ² Within the range of 1 microgram / cm ² ~ 25 microgram / cm ² Within the range of 2 micrograms / cm ² ~ 100 microgram / cm ² Within the range of 2 micrograms / cm ² ~ 75 micrograms / cm ² Within the range of 2 micrograms / cm ² ~ 50 microgram / cm ² Within the range of 2 micrograms / cm ² ~ 30 microgram / cm ² Within the range of 2 micrograms / cm ² ~ 25 microgram / cm ² Or within 2 micrograms / cm ² ~ 20 microgram / cm ² Which is based on the elemental metal content of the oxygen evolution reaction catalyst),
A second gas supply layer comprising an oxygen evolution reaction catalyst (eg, the amount of portion present is at least 0.5 microgram / cm). ² And in some embodiments, 1 microgram / cm ² 1.5 microgram / cm ² 2 microgram / cm ² 2.5 microgram / cm ² 3 microgram / cm ² Or at least 5 micrograms / cm ² And in some embodiments, 0.5 microgram / cm ² ~ 100 microgram / cm ² Within the range of 0.5 microgram / cm ² ~ 75 micrograms / cm ² Within the range of 0.5 microgram / cm ² ~ 50 microgram / cm ² Within the range of 0.5 microgram / cm ² ~ 25 microgram / cm ² Within the range of 1 microgram / cm ² ~ 100 microgram / cm ² Within the range of 1 microgram / cm ² ~ 75 micrograms / cm ² Within the range of 1 microgram / cm ² ~ 50 microgram / cm ² Within the range of 1 microgram / cm ² ~ 25 microgram / cm ² Within the range of 2 micrograms / cm ² ~ 100 microgram / cm ² Within the range of 2 micrograms / cm ² ~ 75 micrograms / cm ² Within the range of 2 micrograms / cm ² ~ 50 microgram / cm ² Within the range of 2 micrograms / cm ² ~ 30 microgram / cm ² Within the range of 2 micrograms / cm ² ~ 25 microgram / cm ² Or within 2 micrograms / cm ² ~ 20 microgram / cm ² Which is based on the elemental metal content of the oxygen evolution reaction catalyst),
A layer comprising an oxygen evolution reaction catalyst (eg, attached) disposed over (eg, attached to) the second major surface of the second gas dispersion layer (eg, the amount of portion present is at least 0.5 microgram / cm). ² And in some embodiments, 1 microgram / cm ² 1.5 microgram / cm ² 2 microgram / cm ² 2.5 microgram / cm ² 3 microgram / cm ² Or at least 5 micrograms / cm ² And in some embodiments, 0.5 microgram / cm ² ~ 100 microgram / cm ² Within the range of 0.5 microgram / cm ² ~ 75 micrograms / cm ² Within the range of 0.5 microgram / cm ² ~ 50 microgram / cm ² Within the range of 0.5 microgram / cm ² ~ 25 microgram / cm ² Within the range of 1 microgram / cm ² ~ 100 microgram / cm ² Within the range of 1 microgram / cm ² ~ 75 micrograms / cm ² Within the range of 1 microgram / cm ² ~ 50 microgram / cm ² Within the range of 1 microgram / cm ² ~ 25 microgram / cm ² Within the range of 2 micrograms / cm ² ~ 100 microgram / cm ² Within the range of 2 micrograms / cm ² ~ 75 micrograms / cm ² Within the range of 2 micrograms / cm ² ~ 50 microgram / cm ² Within the range of 2 micrograms / cm ² ~ 30 microgram / cm ² Within the range of 2 micrograms / cm ² ~ 25 microgram / cm ² Or within 2 micrograms / cm ² ~ 20 microgram / cm ² , Which is based on the elemental metal content of the oxygen evolution reaction catalyst), wherein a membrane electrode assembly is present.
2. The anode catalyst layer
(A) at least one of the elements Au, Co, Fe, Ir, Mn, Ni, Os, Pd, Pt, Rh or Ru,
(B) at least one alloy comprising at least one of Au, Co, Fe, Ir, Mn, Ni, Os, Pd, Pt, Rh or Ru;
(C) at least one composite comprising at least one of Au, Co, Fe, Ir, Mn, Ni, Os, Pd, Pt, Rh or Ru;
(D) at least one oxide, hydrated oxide or hydroxide of at least one of Au, Co, Fe, Ir, Mn, Ni, Os, Pd, Pt, Rh or Ru,
(E) at least one organometallic complex of at least one of Au, Co, Fe, Ir, Mn, Ni, Os, Pd, Pt, Rh or Ru;
(F) at least one carbide of at least one of Au, Co, Fe, Ir, Mn, Ni, Os, Pd, Pt, Rh or Ru,
(G) at least one fluoride of at least one of Au, Co, Fe, Ir, Mn, Ni, Os, Pd, Pt, Rh or Ru;
(H) at least one nitride of at least one of Au, Co, Fe, Ir, Mn, Ni, Os, Pd, Pt, Rh or Ru;
(I) at least one boride of at least one of Au, Co, Fe, Ir, Mn, Ni, Os, Pd, Pt, Rh or Ru;
(J) at least one acid carbide of at least one of Au, Co, Fe, Ir, Mn, Ni, Os, Pd, Pt, Rh or Ru,
(K) at least one oxyfluoride of at least one of Au, Co, Fe, Ir, Mn, Ni, Os, Pd, Pt, Rh or Ru,
(L) at least one oxynitride of at least one of Au, Co, Fe, Ir, Mn, Ni, Os, Pd, Pt, Rh or Ru, or
(M) exemplary comprising at least one of at least one acid boride of at least one of Au, Co, Fe, Ir, Mn, Ni, Os, Pd, Pt, Rh or Ru. The membrane electrode assembly according to embodiment 1.
3. The anode catalyst layer
(A ′) at least one of the elements Al, carbon, Hf, Nb, Re, Si, Sn, Ta, Ti, W or Zr,
(B ′) at least one alloy comprising at least one of Al, carbon, Hf, Nb, Re, Si, Sn, Ta, Ti, W or Zr;
(C ′) at least one composite comprising at least one of Al, carbon, Hf, Nb, Re, Si, Sn, Ta, Ti, W or Zr;
(D ′) at least one oxide of at least one of Al, Hf, Nb, Re, Si, Sn, Ta, Ti, W or Zr,
(E ′) at least one organometallic complex of at least one of Al, Hf, Nb, Re, Si, Sn, Ta, Ti, W or Zr,
(F ′) at least one carbide of at least one of Al, Hf, Nb, Re, Si, Sn, Ta, Ti, W or Zr,
(G ′) at least one fluoride of at least one of Al, carbon, Hf, Nb, Re, Si, Sn, Ta, Ti, W or Zr,
(H ′) at least one nitride of at least one of Al, carbon, Hf, Nb, Re, Si, Sn, Ta, Ti, W or Zr,
(I ′) at least one oxycarbide of at least one of Al, Hf, Nb, Re, Si, Sn, Ta, Ti, W or Zr,
(J ′) at least one oxyfluoride of at least one of Al, Hf, Nb, Re, Si, Sn, Ta, Ti, W or Zr,
(K ′) at least one oxynitride of at least one of Al, carbon, Hf, Nb, Re, Si, Sn, Ta, Ti, W or Zr,
(L ′) at least one boride of at least one of Al, carbon, Hf, Nb, Re, Si, Sn, Ta, Ti, W or Zr, or
(M ′) an exemplary implementation comprising at least one of at least one acid boride of at least one of Al, Hf, Nb, Re, Si, Sn, Ta, Ti, W or Zr The membrane electrode assembly according to Form 1 or 2.
4). 4. The membrane electrode assembly according to any one of exemplary embodiments 1-3, wherein the anode catalyst layer comprises nanostructured whiskers with attached catalyst.
5. The cathode catalyst layer
(A ″) at least one of the elements Au, Co, Fe, Ir, Mn, Ni, Os, Pd, Pt, Rh or Ru,
(B ″) at least one alloy comprising at least one of Au, Co, Fe, Ir, Mn, Ni, Os, Pd, Pt, Rh or Ru;
(C ″) at least one composite comprising at least one of Au, Co, Fe, Ir, Mn, Ni, Os, Pd, Pt, Rh or Ru;
(D ″) at least one oxide of at least one of Au, Co, Fe, Ir, Mn, Ni, Os, Pd, Pt, Rh or Ru,
(E ″) at least one organometallic complex of at least one of Au, Co, Fe, Ir, Mn, Ni, Os, Pd, Pt, Rh or Ru,
(F ″) at least one carbide of at least one of Au, Co, Fe, Ir, Mn, Ni, Os, Pd, Pt, Rh or Ru,
(G ″) at least one fluoride of at least one of Au, Co, Fe, Ir, Mn, Ni, Os, Pd, Pt, Rh or Ru,
(H ″) at least one nitride of at least one of Au, Co, Fe, Ir, Mn, Ni, Os, Pd, Pt, Rh or Ru,
(I ″) at least one boride of at least one of Au, Co, Fe, Ir, Mn, Ni, Os, Pd, Pt, Rh or Ru;
(J ″) at least one acid carbide of at least one of Au, Co, Fe, Ir, Mn, Ni, Os, Pd, Pt, Rh or Ru,
(K ″) at least one oxyfluoride of at least one of Au, Co, Fe, Ir, Mn, Ni, Os, Pd, Pt, Rh or Ru,
(L ″) at least one oxynitride of at least one of Au, Co, Fe, Ir, Mn, Ni, Os, Pd, Pt, Rh or Ru, or
(M ″) including at least one of at least one acid boride of at least one of Au, Co, Fe, Ir, Mn, Ni, Os, Pd, Pt, Rh, or Ru A membrane electrode assembly according to any one of the exemplary embodiments 1-4.
6). The cathode catalyst layer
(A ′ ″) at least one of the elements Al, carbon, Hf, Nb, Re, Si, Sn, Ta, Ti, W or Zr,
(B ′ ″) at least one alloy comprising at least one of Al, carbon, Hf, Nb, Re, Si, Sn, Ta, Ti, W or Zr;
(C ′ ″) at least one composite comprising at least one of Al, carbon, Hf, Nb, Re, Si, Sn, Ta, Ti, W or Zr;
(D ′ ″) at least one oxide of at least one of Al, Hf, Nb, Re, Si, Sn, Ta, Ti, W or Zr,
(E ′ ″) at least one organometallic complex of at least one of Al, Hf, Nb, Re, Si, Sn, Ta, Ti, W or Zr,
(F ″ ′) at least one carbide of at least one of Al, Hf, Nb, Re, Si, Sn, Ta, Ti, W or Zr,
(G ′ ″) at least one fluoride of at least one of Al, carbon, Hf, Nb, Re, Si, Sn, Ta, Ti, W or Zr,
(H ′ ″) at least one nitride of at least one of Al, carbon, Hf, Nb, Re, Si, Sn, Ta, Ti, W or Zr,
(I ′ ″) at least one oxycarbide of at least one of Al, Hf, Nb, Re, Si, Sn, Ta, Ti, W or Zr,
(J ′ ″) at least one oxyfluoride of at least one of Al, Hf, Nb, Re, Si, Sn, Ta, Ti, W or Zr,
(K ′ ″) at least one oxynitride of at least one of Al, carbon, Hf, Nb, Re, Si, Sn, Ta, Ti, W or Zr,
(L ′ ″) at least one boride of at least one of Al, carbon, Hf, Nb, Re, Si, Sn, Ta, Ti, W or Zr, or
(M ′ ″) including at least one of at least one acid boride of at least one of Al, Hf, Nb, Re, Si, Sn, Ta, Ti, W or Zr, Embodiment 6. The membrane electrode assembly according to any one of Embodiments 1 to 5.
7). 7. The membrane electrode assembly according to any one of exemplary embodiments 1-6, wherein the cathode catalyst layer comprises nanostructured whiskers with attached catalyst.
8). The membrane electrode assembly has the following conditions:
(A) at least one of the plurality of layers comprising the oxygen evolution reaction catalyst is 1: 1 or less (in some embodiments, 0.9: 1 or less, 0.8: 1 or less, 0.75: 1 0.7: 1 or less, 0.6: 1 or less, 0.5: 1 or less, 0.4: 1 or less, 0.3: 1 or less, 0.25: 1 or less, 0.2: 1 or less Or the ratio of elemental metal Pt to elemental metal oxygen evolution reaction catalyst (ie, RuO or less than 0.1: 1 or even 0: 1 or less) (ie, RuO ₂ Is the oxygen evolution reaction catalyst, the ratio of the number of Pt atoms to the number of Ru atoms), or
(B) on at least one of the first gas supply layer, the second gas supply layer, the optional first gas dispersion layer or the optional second gas dispersion layer comprising an oxygen evolution reaction catalyst At least one of the layers disposed in the layer is 1: 1 or less (in some embodiments, 0.9: 1 or less, 0.8: 1 or less, 0.75: 1 or less, 0.7: 1 Or less, 0.6: 1 or less, 0.5: 1 or less, 0.4: 1 or less, 0.3: 1 or less, 0.25: 1 or less, 0.2: 1 or less, or 0.1 Example Embodiments 1 to 7 satisfying at least one of the following conditions: the ratio of the elemental metal Pt to the elemental metal oxygen evolution reaction catalyst is 1: 1 or even 0: 1 or less) The membrane electrode assembly according to any one of the above.
9. The first gas dispersion layer has a first main surface and a second main surface substantially opposed to each other, and the second main surface of the first gas supply layer is formed by the second main surface of the first gas dispersion layer. 9. The membrane electrode assembly according to any one of exemplary embodiments 1-8, which is also closer to the first major surface of the first gas dispersion layer.
10. The first gas supply layer is substantially free of Pt (ie, 0.1 microgram / cm). ² Less than Pt), the membrane electrode assembly according to exemplary embodiment 9.
11. The second gas dispersion layer has a first main surface and a second main surface that are substantially opposed to each other, and the second main surface of the cathode catalyst layer is second than the second main surface of the second gas dispersion layer. The membrane electrode assembly according to any one of Exemplary Embodiments 1-10, closer to the first major surface of the gas dispersion layer.
12 The second gas supply layer is substantially free of Pt (ie, 0.1 microgram / cm). ² Less), the membrane electrode assembly according to exemplary embodiment 11.
13. An electrochemical device comprising at least one of the membrane electrode assemblies according to any one of exemplary embodiments 1-12.
14 The electrochemical device according to exemplary embodiment 13, wherein the electrochemical device is a fuel cell.

  The advantages and embodiments of the present invention are further illustrated by the following examples, although the specific materials and amounts thereof described in these examples, as well as other conditions and details, should not unduly limit the present invention. Should not be interpreted. All parts and ratios are based on weight unless otherwise specified.

EXAMPLES Membrane Electrode Assembly (MEA) Preparation All MEAs in the Examples and Comparative Examples are available from 3M Company (St. Paul, MN, USA) as the same perfluorinated sulfonic acid membrane (“825 EW ionomer”) with a nominal equivalent of 825. ). The thickness of this film was about 24 micrometers. The cathode catalyst layer was prepared from a dispersed Pt catalyst (with a loading of 400 micrograms / cm ² ) by using a transfer method well known in the art. G. 5. , Weinheim: Wiley-VCH; 1997 or Wilson and Gottesfeld, J Appl. Electrochem. 1992, 22: 1-7, the disclosures of which are incorporated herein by reference.

The gas diffusion layer (GDL) was produced by coating one side of a carbon paper electrode backing layer (obtained from Mitsubishi Rayon Co., Ltd., Tokyo) with a gas diffusion layer / microporous layer (MPL). The microporous layer was prepared using a coating / impregnation process as generally described in US Pat. No. 6,465,041 (Frisk et al.), The disclosure of which is incorporated herein by reference. The impregnation method included the following steps. The alcohol suspension was carbon black powder with a final loading of 1.5 milligrams / cm ² (obtained from Cabot Corporation (Boston, Mass., USA) under the name “VULCAN XC-72”) and 10 weight percent The polytetrafluoroethylene emulsion (obtained from EI du Pont de Nemours (Wilmington, Del.)) Under the trade name "Teflon" The mixture was thoroughly stirred using an apparatus, and then impregnated into carbon paper to form a precursor of a microporous layer. The precursor microporous layer was first fired at 240 ° C. for about 30 minutes and then sintered at 350 ° C. for about 40 minutes to form a microporous layer.

177 ° C (350 ° F), 1.0 MPa (150 psig) using a laminator (obtained from Cheminstruments Inc. (West Chester, Ohio, USA) under the name "CHEMINSTRUMENTS HL-101 DUAL HEAT ROLL LAMINATOR") A membrane electrode assembly was fabricated using the following lamination method at 36.5 centimeters (1.2 feet) per minute. In this method, the laminator is fed in the following order: paper (obtained from “HAMMERMIL 122549” International Paper, Memphis, Tennessee, USA), PEM coated polyimide release liner with the PEM coated surface facing away from the paper. (Obtained from EI du Pont de Nemours under the trade name “KAPTON HN”), a catalyst coated polyimide release liner (“KAPTON HN”) with a catalyst layer facing the PEM coated surface and a second paper (“ The elements were stacked and supplied in the order of HAMMERMILL 122549 ”). Next, immediately after lamination, the sample was peeled from both liners to obtain an electrolyte membrane with one-side catalyst layer (CCM). Place the CCM between fluoropolymer sheets (obtained from EI du Pont de Nemours under the trade name “Teflon”) and place on a flat surface to prevent dirt from contaminating the membrane and opening holes. In a plastic bag. Prior to building the MEA, CCM was cut into 4 inch square (10.16 cm square) samples and mounting holes were made outside the central 50 cm ² active area to aid assembly.

  The anode catalyst described in the following examples and comparative examples has a similar five-layer membrane electrode assembly configuration in the following layer order: gas diffusion layer, electrode, polymer electrolyte membrane (PEM), electrode and gas diffusion layer. Prepared. A microporous layer coated on the gas diffusion layer was between the gas diffusion layer and the electrode, resulting in a seven-layer configuration. As Comparative Example C, the anode electrode had two layers: a nanostructured thin film oxygen evolution reaction catalyst layer and Pt dispersed on the carbon layer.

MEA Evaluation Method The following examples and comparative examples were installed in a 50 cm ² cell having four meandering flow fields at a compression rate of about 10%, and under the protocol and fuel cell performance test prepared in advance for trial operation. Made it work. The test site was obtained from Fuel Cell Technology (Albuquerque, NM). For this test method, during the conditioning, the oxygen generating reaction catalyst was operated as a cathode and a series of about 14 thermal cycles (details of the thermal cycle are described in the 2010 DOE Hydrogen Program Review, Advance Cathode Catalysts and Supports for PEM Fuel). Cells, Debe, June 8, 2010 (http://www.hydrogen.energy.gov/pdfs/review10/fc001_debe_2010_o_web.pdf, the disclosure of which is hereby incorporated by reference) (October 1st, 2014, 9:37 am (Chubu Standard Time)) was executed, and the OER catalyst and MEA were commissioned. During actual cell operation, including injection cycle testing, the OER catalyst was operated as the anode: the cell set point was 75 ° C. cell temperature, 68 ° C. inlet dew point, 800 sccm hydrogen anode flow, 68 ° C. At the inlet dew point, the cathode flow setpoint was 1800 sccm and the outlet was at atmospheric pressure, and during the thermal cycle, the electrokinetic scan was performed three times at 0.9 to 0.3 volts, so that the MEA to be tested was “Thermal cycling” has been found to be useful in sweeping out impurities and quickly bringing thin film electrode performance to a certain level.

  Next, the OER effectiveness durability time of the anode catalyst was evaluated. OER effectiveness lifetime was expressed as the time that the OER catalyst can hold the voltage below a given level at a given current. The OER efficacy durability time was evaluated under nitrogen humidified to 70 ° C. to full saturation.

  Gas switching is done with two different dedicated fields, keeping all other test field parameters constant at cell temperature: 68 ° C., cathode air flow: 1800 sccm air, inlet: RH 70% and outlet pressure: 138 kPa gauge pressure. This was accomplished by alternating the reactant (OER catalyst) on the anode from hydrogen to air (oxygen is the reactant) using a flow regulator. This was in contrast to the use of conventional fuel cells where the anode reactant gas is hydrogen. The degree of damage caused to the anode and / or cathode during start / stop (SU / SD) was a function of the number of conversions from one anode gas to another. When the anode gas changed from hydrogen to air (oxygen), the voltage across the cell went from about 0.9 volts to 0 volts. The gas flow was switched from 280 sccm air for 20 seconds to 800 sccm hydrogen for 15 seconds and back again. In this particular test, this series of steps was repeated until the desired number of gas switching events, referred to herein as a gas cycle, was obtained. In the examples tested under the evaluation method, the number of gas switching was 400 times.

Comparative Example A
Preparation of Nanostructured Whisker Perylene Red Pigment (CI Pigment Red 149, “PR149” as described in US Pat. No. 4,812,352 (Debe), the disclosure of which is incorporated herein by reference. A layer of Clariant (obtained from Charlotte, North Carolina, USA), also known as “, is thermally annealed, and this is sublimated onto a microstructured catalyst transfer polymer substrate (MCTS) (nominal coating thickness 200 nm). Nanostructured whiskers were prepared by coating. In these examples, 90/3/3 (angle (degrees) / distance between peaks (micrometers) / height of most peaks or long repeat features (micrometers)) and 120/5/0 Using. All MCTS structures had a surface area of 2 times the square root, similar to the Debe patent. After coating, after coating the perylene red coating, the roll product is annealed under reduced pressure in a line process, thereby forming whiskers as described in the above patent.
Preparation of nanostructured thin film (NSTF) catalyst layer

  A nanostructured thin film (NSTF) catalyst layer was prepared by sputter-coating Pt, Ru and Ir catalyst films sequentially on a layer of nanostructured whiskers using a DC-magnetron sputtering process. The relative thickness of each layer was varied as needed.

Four cryopumps (obtained from Austin Scientific, Oxford Instruments, Austin, Tex.), Turbopump, typical Ar sputter gas pressure of about 0.66 Pa, 5 cm x 25.4 cm (2 in x 10 in) rectangle A vacuum sputter deposition system (obtained as Model Custom Research from Mille Lane Engineering Co., USA) equipped with a sputter target (obtained from Sophisticated Alloys, Inc. (Butler, PA, USA)) was used. Prior to deposition, the sputtering chamber was evacuated to a base pressure of 9.3 × 10 ⁻⁶ Pa (7 × 10 ⁻⁷ Torr). The coating was deposited by using ultra high purity Ar as the sputtering gas and magnetron power in the range of 30-300 Watts. High purity (99.9 +%), Pt, Ir and Ru were used for the sputtering target. Each target was pre-sputtered to clean the surface before vapor deposition. The substrate to be sputtered was placed away from the sputtering target. Each target is then struck for a given time to remove any contamination that may form on the target surface when the system is exposed to atmospheric pressure to contain the sample. First, a Pt layer is coated directly onto the nanostructured whiskers to carry about 20 micrograms / cm ² of Pt. An Ir catalyst top layer was then sputter deposited onto the Pt layer to support 15 micrograms / cm ² of Ir.

  To prepare the comparative example A membrane electrode assembly (MEA), NSTF catalyst was used as the anode. Using the above-mentioned MEA evaluation method, the OER effectiveness durability time of the MEA of Comparative Example A was tested. The cell voltage increased from an initial value of about 1.68 volts to 2.2 volts after about 5000 seconds.

Comparative Example B
Comparative Example B was prepared as described in Comparative Example A except that after supporting 20 microgram / cm ² of Pt on the NSTF catalyst, Zr of 16 microgram / cm ² was supported, and then Zr The Ir layer is supported at an Ir loading amount of 15 microgram / cm ² . The OER effectiveness durability time of Comparative Example B was tested using the MEA evaluation method described above. The results are plotted in FIG.

Comparative Example C
Preparation of 25 microgram / cm ² dispersed catalyst The raw materials used were 50 wt% Pt-supported carbon catalyst powder (commercially available from NE CHEMCAT (Tokyo) under the trade name “SA50BK”), 60/40 n-propyl alcohol. 825 equivalents of perfluorosulfonic acid ionomer (commercially available under the trade name “3M825” from St. Paul, Minn., USA) with a solids content of 20% in water, and an ink with a total solids content of 12 wt% To form additional n-propyl alcohol (nPa) and water. The raw materials were mixed together in a polyethylene bottle to form an ink. A 250 gram bottle was used for 100-200 gram ink. The ink blend should contain 5% to 25% solids for a coatable viscosity, and the solids content wt% is adjusted by adding nPa and water to the ink. A mixed medium consisting of 6 millimeter zirconia beads (obtained from Zircoa (Solon, Ohio, USA) under the name "ZIRBEADS") was added at a weight ratio of 1-4 times the weight of the ink. The ink was then rolled at 30 to 180 revolutions per minute for 4 to 96 hours to ensure proper mixing and homogeneity of the ink. This was then used with a Mayer bar (obtained from Industry Tech (Oldsmer, Florida, USA)) numbered 36-72 (3.6-7.2 mils, where 1 mil = 25.4 micrometers). The ink was coated on a release liner. Standard release liners have release characteristics that allow ink to be easily applied and subsequently dried to facilitate removal of subsequently applied material by methods involving lamination to another substrate such as a film. It is the base material which has. In order to obtain the desired catalyst loading (eg 400 micrograms of Pt / cm ² ), the Mayer bar number for coating must be adjusted. Next, the release liner + wet ink coating was dried at 75 ° C. to 150 ° C. for 3 to 10 minutes to obtain the dry electrode composite described in this work.

Comparative Example C was adjusted as described in Comparative Example A. However, NSTF catalyst Zr was supported at 16 microgram / cm ² , and then 15 microgram / cm ² of Ir was supported, and then a Pt-dispersed catalyst was again laminated on the whisker at a supported amount of 25 microgram / cm ^2. Different points. This restacking deviates from the membrane electrode assembly (MEA) preparation and replaces the “PEM on liner” layer of the stack with a laminated electrolyte membrane with one-sided catalyst layer on the liner and conditions are 177 ° C. ( 350 ° F), 1.0 MPA (100 psig), feed rate adjusted to 36.5 centimeters / minute (1.2 feet per minute).

  The OER effectiveness durability time of Comparative Example C was tested using the MEA evaluation method described above. The results are plotted in FIG.

FIG. 3 shows test data from repeated MEAs of Comparative Examples A-C and MEA with Ir deposited on the GDL microporous layers listed in Examples 1-6. In accordance with the MEA evaluation method described above, these MEAs were incorporated into fuel cells that were tested for OER endurance time of cell reversal. The vertical axis of FIG. 3 shows the cell output voltage as a function of time for the standard hydrogen electrode _ESHE for various MEAs in the test cell. In this test, it was desirable to keep the cell voltage below 1.7 volts as much as possible. A membrane electrode assembly was prepared according to the MEA preparation procedure described above. The carbon paper gas diffusion layers on the anode side and cathode side included fluoropolymer microporous layers (gas diffusion microlayers) facing the respective anode catalyst layer and cathode catalyst layer. The hydrogen reduction reaction (HRR) catalyst Pt was incorporated in the anode catalyst layer on the polymer electrolyte membrane as described later.

In Examples 1-6, an oxygen evolution reaction (OER) catalyst, here Ir, was deposited on a microporous layer of GDL to form a catalyst coated backing (CCB). In the comparative example, an Ir OER catalyst was incorporated directly into the anode catalyst layer on the PEM. In Comparative Example B (CE-B) and Comparative Example C (CE-C) and Example 2 (E2), Example 3 (E3), Example 5 (E5) and Example 6 (E6), Zr or Zr A layer of / Hf was deposited along Ir OER catalyst. In Comparative Example CE-B, a planar equivalent thickness of 250 angstroms (25 nanometers) Zr layer was deposited on the nanostructured whisker layer with a surface roughness coefficient (surface area augmentation factor) of about 10 to achieve physical properties. In particular, an effect of separating Pt and Ir on the whisker on an atomic scale (typically, a distance of 5 to 10 nanometers) was obtained. Examples 1-6 were prepared as described in Comparative Example A. However, the instructions and comments listed in the table below are different.

  It will be apparent to those skilled in the art that modifications and variations can be made to the disclosure without departing from the scope and spirit of the invention. The present invention should not be limited to the embodiments described herein for purposes of illustration.

Claims (14)

A first gas supply layer;
Optionally a first gas dispersion layer;
An anode catalyst layer comprising a first catalyst;
A membrane,
A cathode catalyst layer comprising a second catalyst;
Optionally a second gas dispersion layer;
A second gas supply layer in order,
The first gas supply layer has a first main surface and a second main surface which are substantially opposed to each other;
The anode catalyst layer has a first main surface and a second main surface that are substantially opposed to each other, and the second main surface of the first gas supply layer is more than the second main surface of the anode catalyst layer. Closer to the first major surface of the anode catalyst layer;
The membrane has a first main surface and a second main surface that are substantially opposed to each other, and the second main surface of the anode catalyst layer is more than the second main surface of the membrane than the first main surface of the membrane. Closer to the surface,
The cathode catalyst layer has a first main surface and a second main surface that are substantially opposed to each other, and the second main surface of the membrane is more than the second main surface of the cathode catalyst layer. Closer to the first main surface,
The second gas supply layer has a first main surface and a second main surface that are substantially opposed to each other, and the second main surface of the cathode catalyst layer is the second main surface of the second gas supply layer. Closer to the first main surface of the second gas supply layer than to the surface,
At least one of the following layers:
A layer containing an oxygen generation reaction catalyst disposed on the first main surface of the first gas supply layer;
The first gas supply layer containing an oxygen generation reaction catalyst;
A layer containing an oxygen generation reaction catalyst disposed on the second main surface of the first gas supply layer;
A layer containing an oxygen generation reaction catalyst disposed between the first gas supply layer and the first gas dispersion layer;
A layer containing an oxygen generation reaction catalyst disposed on the first main surface of the first gas dispersion layer;
The first gas dispersion layer containing an oxygen generation reaction catalyst;
A layer containing an oxygen generation reaction catalyst disposed on the second main surface of the first gas dispersion layer;
A layer containing an oxygen generation reaction catalyst disposed on the first main surface of the second gas dispersion layer;
The second gas dispersion layer containing an oxygen generation reaction catalyst;
A layer containing an oxygen generation reaction catalyst disposed on the second main surface of the second gas dispersion layer;
A layer containing an oxygen generation reaction catalyst disposed between the second gas supply layer and the second gas dispersion layer;
A layer containing an oxygen generation reaction catalyst disposed on the first main surface of the second gas supply layer;
The second gas supply layer containing an oxygen generation reaction catalyst;
A membrane electrode assembly wherein there is at least one of a layer comprising an oxygen evolution reaction catalyst disposed on the second major surface of the second gas supply layer. The anode catalyst layer is
(A) at least one of the elements Au, Co, Fe, Ir, Mn, Ni, Os, Pd, Pt, Rh or Ru,
(B) at least one alloy comprising at least one of Au, Co, Fe, Ir, Mn, Ni, Os, Pd, Pt, Rh or Ru;
(C) at least one composite comprising at least one of Au, Co, Fe, Ir, Mn, Ni, Os, Pd, Pt, Rh or Ru;
(D) at least one oxide of at least one of Au, Co, Fe, Ir, Mn, Ni, Os, Pd, Pt, Rh or Ru,
(E) at least one organometallic complex of at least one of Au, Co, Fe, Ir, Mn, Ni, Os, Pd, Pt, Rh or Ru;
(F) at least one carbide of at least one of Au, Co, Fe, Ir, Mn, Ni, Os, Pd, Pt, Rh or Ru,
(G) at least one fluoride of at least one of Au, Co, Fe, Ir, Mn, Ni, Os, Pd, Pt, Rh or Ru;
(H) at least one nitride of at least one of Au, Co, Fe, Ir, Mn, Ni, Os, Pd, Pt, Rh or Ru;
(I) at least one boride of at least one of Au, Co, Fe, Ir, Mn, Ni, Os, Pd, Pt, Rh or Ru;
(J) at least one acid carbide of at least one of Au, Co, Fe, Ir, Mn, Ni, Os, Pd, Pt, Rh or Ru,
(K) at least one oxyfluoride of at least one of Au, Co, Fe, Ir, Mn, Ni, Os, Pd, Pt, Rh or Ru,
(L) At least one oxynitride of at least one of Au, Co, Fe, Ir, Mn, Ni, Os, Pd, Pt, Rh, or Ru, or (m) Au, Co, Fe, Ir, At least one acid boride of at least one of Mn, Ni, Os, Pd, Pt, Rh or Ru,
The membrane electrode assembly according to claim 1, comprising at least one of: The anode catalyst layer is
(A ′) at least one of the elements Al, carbon, Hf, Nb, Re, Si, Sn, Ta, Ti, W or Zr,
(B ′) at least one alloy comprising at least one of the elements Al, carbon, Hf, Nb, Re, Si, Sn, Ta, Ti, W or Zr;
(C ′) at least one composite comprising at least one of Al, carbon, Hf, Nb, Re, Si, Sn, Ta, Ti, W or Zr;
(D ′) at least one oxide of at least one of Al, Hf, Nb, Re, Si, Sn, Ta, Ti, W or Zr,
(E ′) at least one organometallic complex of at least one of Al, Hf, Nb, Re, Si, Sn, Ta, Ti, W or Zr,
(F ′) at least one carbide of at least one of Al, Hf, Nb, Re, Si, Sn, Ta, Ti, W or Zr,
(G ′) at least one fluoride of at least one of Al, carbon, Hf, Nb, Re, Si, Sn, Ta, Ti, W or Zr,
(H ′) at least one nitride of at least one of Al, carbon, Hf, Nb, Re, Si, Sn, Ta, Ti, W or Zr,
(I ′) at least one oxycarbide of at least one of Al, Hf, Nb, Re, Si, Sn, Ta, Ti, W or Zr,
(J ′) at least one oxyfluoride of at least one of Al, Hf, Nb, Re, Si, Sn, Ta, Ti, W or Zr,
(K ′) at least one oxynitride of at least one of Al, carbon, Hf, Nb, Re, Si, Sn, Ta, Ti, W or Zr,
(L ′) at least one boride of at least one of Al, carbon, Hf, Nb, Re, Si, Sn, Ta, Ti, W or Zr, or (m ′) Al, Hf, Nb, Re At least one acid boride of at least one of Si, Sn, Ta, Ti, W or Zr,
The membrane electrode assembly according to claim 1 or 2, comprising at least one of the following.   The membrane electrode assembly according to any one of claims 1 to 3, wherein the anode catalyst layer comprises nanostructured whiskers to which the catalyst is attached. The cathode catalyst layer is
(A ″) at least one of the elements Au, Co, Fe, Ir, Mn, Ni, Os, Pd, Pt, Rh or Ru,
(B ″) at least one alloy comprising at least one of Au, Co, Fe, Ir, Mn, Ni, Os, Pd, Pt, Rh or Ru;
(C ″) at least one composite comprising at least one of Au, Co, Fe, Ir, Mn, Ni, Os, Pd, Pt, Rh or Ru;
(D ″) at least one oxide of at least one of Au, Co, Fe, Ir, Mn, Ni, Os, Pd, Pt, Rh or Ru,
(E ″) at least one organometallic complex of at least one of Au, Co, Fe, Ir, Mn, Ni, Os, Pd, Pt, Rh or Ru,
(F ″) at least one carbide of at least one of Au, Co, Fe, Ir, Mn, Ni, Os, Pd, Pt, Rh or Ru,
(G ″) at least one fluoride of at least one of Au, Co, Fe, Ir, Mn, Ni, Os, Pd, Pt, Rh or Ru,
(H ″) at least one nitride of at least one of Au, Co, Fe, Ir, Mn, Ni, Os, Pd, Pt, Rh or Ru,
(I ″) at least one boride of at least one of Au, Co, Fe, Ir, Mn, Ni, Os, Pd, Pt, Rh or Ru;
(J ″) at least one acid carbide of at least one of Au, Co, Fe, Ir, Mn, Ni, Os, Pd, Pt, Rh or Ru,
(K ″) at least one oxyfluoride of at least one of Au, Co, Fe, Ir, Mn, Ni, Os, Pd, Pt, Rh or Ru,
(L ″) at least one oxynitride of Au, Co, Fe, Ir, Mn, Ni, Os, Pd, Pt, Rh or Ru, or (m ″) Au, Co, At least one acid boride of at least one of Fe, Ir, Mn, Ni, Os, Pd, Pt, Rh or Ru,
The membrane electrode assembly according to any one of claims 1 to 4, comprising at least one of the following. The cathode catalyst layer is
(A ′ ″) at least one of the elements Al, carbon, Hf, Nb, Re, Si, Sn, Ta, Ti, W or Zr,
(B ′ ″) at least one alloy comprising at least one of Al, carbon, Hf, Nb, Re, Si, Sn, Ta, Ti, W or Zr;
(C ′ ″) at least one composite comprising at least one of Al, carbon, Hf, Nb, Re, Si, Sn, Ta, Ti, W or Zr;
(D ′ ″) at least one oxide of at least one of Al, Hf, Nb, Re, Si, Sn, Ta, Ti, W or Zr,
(E ′ ″) at least one organometallic complex of at least one of Al, Hf, Nb, Re, Si, Sn, Ta, Ti, W or Zr,
(F ″ ′) at least one carbide of at least one of Al, Hf, Nb, Re, Si, Sn, Ta, Ti, W or Zr,
(G ′ ″) at least one fluoride of at least one of Al, carbon, Hf, Nb, Re, Si, Sn, Ta, Ti, W or Zr,
(H ′ ″) at least one nitride of at least one of Al, carbon, Hf, Nb, Re, Si, Sn, Ta, Ti, W or Zr,
(I ′ ″) at least one oxycarbide of at least one of Al, Hf, Nb, Re, Si, Sn, Ta, Ti, W or Zr,
(J ′ ″) at least one oxyfluoride of at least one of Al, Hf, Nb, Re, Si, Sn, Ta, Ti, W or Zr,
(K ′ ″) at least one oxynitride of Al, carbon, Hf, Nb, Re, Si, Sn, Ta, Ti, W or Zr,
(L ′ ″) at least one boride of at least one of Al, carbon, Hf, Nb, Re, Si, Sn, Ta, Ti, W or Zr, or (m ′ ″) Al, Hf At least one acid boride of at least one of Nb, Re, Si, Sn, Ta, Ti, W or Zr,
The membrane electrode assembly according to any one of claims 1 to 5, comprising at least one of the following.   The membrane electrode assembly according to any one of claims 1 to 6, wherein the cathode catalyst layer comprises nanostructured whiskers to which the catalyst is attached. The membrane electrode assembly comprises:
(A) At least one of the plurality of layers including the oxygen generation reaction catalyst has a ratio of the element metal Pt to the element metal oxygen generation reaction catalyst of 1: 1 or less, or (b) the oxygen generation reaction catalyst The first gas supply layer, the second gas supply layer, the optional first gas dispersion layer, or the optional second gas dispersion layer disposed on at least one of 8. At least one of the layers comprises at least one of having a ratio of elemental metal Pt to elemental metal oxygen evolution reaction catalyst of 1: 1 or less, according to any one of claims 1-7. Membrane electrode assembly.   The first gas dispersion layer has a first main surface and a second main surface that are substantially opposed to each other, and the second main surface of the first gas supply layer is the first gas dispersion layer of the first gas dispersion layer. The membrane electrode assembly according to any one of claims 1 to 8, which is closer to the first main surface of the first gas dispersion layer than to the second main surface.   The membrane electrode assembly according to claim 9, wherein the first gas supply layer is substantially free of Pt.   The second gas dispersion layer has a first main surface and a second main surface that are substantially opposed to each other, and the second main surface of the cathode catalyst layer is the second main surface of the second gas dispersion layer. The membrane electrode assembly according to any one of claims 1 to 10, which is closer to the first main surface of the second gas dispersion layer than to a surface.   The membrane electrode assembly according to claim 11, wherein the second gas supply layer is substantially free of Pt.   An electrochemical device comprising at least one of the membrane electrode assemblies according to any one of claims 1-12.   The electrochemical device according to claim 13, wherein the electrochemical device is a fuel cell.

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